hotfix: changed DomRobot API behaviour

no persistent status file was written in case of an error as the return status code was always 0

.gitchangelog.rc

@@ -158,7 +158,7 @@ body_process = ReSub(r'((^|\n)[A-Z]\w+(-\w+)*: .*(\n\s+.*)*)+$', r'') | strip
 ##
 ## Available constructs are those listed in ``body_process`` doc.
 subject_process = (strip |
-    ReSub(r'^([cC]hg|[fF]ix|[nN]ew)\s*:\s*((dev|use?r|pkg|test|doc)\s*:\s*)?([^\n@]*)(@[a-z]+\s+)*$', r'\4') |
+    ReSub(r'^([cC]hg|[fF]ix|[nN]ew|[dD]oc|[fF]eat|[aA]dd|[cC]hange)\s*:\s*((dev|use?r|pkg|test|doc)\s*:\s*)?([^\n@]*)(@[a-z]+\s+)*$', r'\4') |
     SetIfEmpty("No commit message.") | ucfirst | final_dot)
 
 

.gitignore

@@ -1,2 +1,3 @@
 .env*
 docker-compose*
+.vscode

CHANGELOG.md

@@ -1,127 +1,228 @@
 # Changelog
 
 
+## 0.5.3 (2023-02-26)
+
+### Fix
+
+* Set constant alpine version as latest couses issues. [Eduard Veit]
+
+
+## 0.5.2 (2023-02-26)
+
+### Fix
+
+* Incorrect dns ip handling via domrobot. [Eduard Veit]
+
+
+## 0.5.1 (2022-11-21)
+
+### Features
+
+* Use provider checkip API. [Eduard Veit]
+
+### Fix
+
+* Handle some curl exit codes. [Eduard Veit]
+
+
+## 0.5.0 (2022-11-10)
+
+### Features
+
+* Use provider DNS servers. [Eduard Veit]
+
+* Temporarily disable an ip version if the connectivity/routing does not work. [Eduard Veit]
+
+### Documentation
+
+* 📝 update default values in table. [Eduard Veit]
+
+
+## 0.4.0 (2022-11-07)
+
+### Features
+
+* ✨ add support for dynu.com as DynDNS2 provider. [Eduard Veit]
+
+### Documentation
+
+* 📝 add dynu.com as DynDNS2 provider. [Eduard Veit]
+
+
+## 0.3.5 (2022-11-03)
+
+### Features
+
+* ✨ add support for IPv64.net as DynDNS2 provider. [Eduard Veit]
+
+### Fix
+
+* Delete status file after success. [Eduard Veit]
+
+* More status file issues. [Eduard Veit]
+
+* Incorrect status code handling. [Eduard Veit]
+
+  no persistent status file was written in case of an error as the return status code was always 0
+
+### Documentation
+
+* 📝 change TTL to 60 for IPv64.net. [Eduard Veit]
+
+* 📝 add IPv64.net as DynDNS2 provider. [Eduard Veit]
+
+
+## 0.3.4 (2022-06-30)
+
+### Features
+
+* ✨ add support for ddnss.de as DynDNS2 provider. [Eduard Veit]
+
+### Documentation
+
+* 📝 update providers in README. [Eduard Veit]
+
+
+## 0.3.3 (2022-06-07)
+
+### Fix
+
+* Wrong parameter name for DuckDNS. [Eduard Veit]
+
+### Documentation
+
+* 📝 add comments to docker-compose.yml example. [Eduard Veit]
+
+
+## 0.3.2 (2022-05-26)
+
+### Features
+
+* ✨ add tzdata to Dockerfile for timezone config. [Eduard Veit]
+
+  You can now set your timezone with the environment variable
+  `TZ="Europe/Berlin"`
+
+
+## 0.3.1 (2022-05-26)
+
+### Fix
+
+* 🐛 curl/libcurl doesn't support dns-server option. [Eduard Veit]
+
+  the latest alpine we are using for the docker image
+  does also drops the support for that option like debian/ubuntu/etc
+
+
+## 0.3.0 (2022-05-26)
+
+### Features
+
+* ✨ validate ip address respons from ip check web service. [Eduard Veit]
+
+* ✨ check internet connection for selected ip versions. [Eduard Veit]
+
+* 🎨 colorful info, debug and error messages. [Eduard Veit]
+
+### Fix
+
+* Abort on all dig errors. [Eduard Veit]
+
+### Documentation
+
+* 📝 add labels to Dockerfile. [Eduard Veit]
+
+
 ## 0.2.0 (2021-09-24)
 
-### New
+### Features
 
-* :sparkles: enable parameter extensions for `docker run --interactive` [Eduard Veit]
+* ✨ enable parameter extensions for `docker run --interactive` [Eduard Veit]
 
-* :sparkles: add pre-commit hooks for markdown. [Eduard Veit]
+### Changed
 
-* :sparkles: change git hooks and add shfmt. [Eduard Veit]
+* Handle dns server selection. [Eduard Veit]
-
-* :sparkles: add pre-commit git hook for shellcheck. [Eduard Veit]
-
-### Changes
-
-* :wrench: remove md-toc from pre-commit. [Eduard Veit]
-
-* :wrench: handle dns server selection. [Eduard Veit]
 
 ### Documentation
 
-* :memo: update CHANGELOG.md. [Eduard Veit]
+* 📝 update CHANGELOG.md. [Eduard Veit]
 
-* :memo: document docker parameters. [Eduard Veit]
+* 📝 document docker parameters. [Eduard Veit]
 
-* :memo: change default dns server setting. [Eduard Veit]
+* 📝 change default dns server setting. [Eduard Veit]
 
-* :memo: update CHANGELOG. [Eduard Veit]
+* 📝 update CHANGELOG. [Eduard Veit]
 
-* :memo: update README.md. [Eduard Veit]
+* 📝 update README.md. [Eduard Veit]
-
-### Other
-
-* :art: lint README.md. [Eduard Veit]
-
-* :art: add shfmt params to pre-commit check. [Eduard Veit]
-
-* :art: fix shell style. [Eduard Veit]
-
-* :recycle: seperate parsing logic. [Eduard Veit]
-
-* :recycle: normalizing pre-commit configuration to a top-level map. [Eduard Veit]
-
-* :recycle: refactorings. [Eduard Veit]
-
-* Refactor: :recycle: remove unused help message. [Eduard Veit]
 
 
 ## 0.1.2 (2021-04-23)
 
 ### Documentation
 
-* :memo: document environment variables. [Eduard Veit]
+* 📝 document environment variables. [Eduard Veit]
-
-### Other
-
-* :recycle: refactor: method extractions and other beautifications. [Eduard Veit]
 
 
 ## 0.1.1 (2021-04-23)
 
 ### Fix
 
-* :bug: fix loop and error handling in case of connection issues. [Eduard Veit]
+* 🐛 fix loop and error handling in case of connection issues. [Eduard Veit]
 
 
 ## 0.1.0 (2021-04-22)
 
-### New
+### Features
 
-* :sparkles: add Dockerfile. [Eduard Veit]
+* ✨ add Dockerfile. [Eduard Veit]
 
-* :sparkles: add loop mode. [Eduard Veit]
+* ✨ add loop mode. [Eduard Veit]
 
-* :sparkles: add support for Duck DNS as DynDNS2 provider. [Eduard Veit]
+* ✨ add support for Duck DNS as DynDNS2 provider. [Eduard Veit]
 
-* :sparkles: add support for deSEC as DynDNS2 provider. [Eduard Veit]
+* ✨ add support for deSEC as DynDNS2 provider. [Eduard Veit]
 
-* :sparkles: add completion. [Eduard Veit]
+* ✨ add completion. [Eduard Veit]
 
-  :sparkles: add man page
+  ✨ add man page
 
-* :sparkles: replace getopt with argbash. [Eduard Veit]
+* 🔃 replace getopt with argbash. [Eduard Veit]
 
-* :sparkles: add interpretaton of status codes and act accordingly. [Eduard Veit]
+* ✨ add interpretaton of status codes and act accordingly. [Eduard Veit]
 
-* :sparkles: make network interface configurable. [Eduard Veit]
+* ✨ make network interface configurable. [Eduard Veit]
 
-* :sparkles: add DynDNS2 support for dynv6.com. [Eduard Veit]
+* ✨ add DynDNS2 support for dynv6.com. [Eduard Veit]
 
-* :sparkles: add .gitchangelog.rc. [Eduard Veit]
+### Added
 
-* :sparkles: add dynb.sh. [Eduard Veit]
+* 📝 README.md. [Eduard Veit]
+
+* ✨ dynb.sh. [Eduard Veit]
+
+### Changed
+
+* 🔃 rename environment variables. [Eduard Veit]
 
 ### Fix
 
-* :bug: fix sourcing of config file. [Eduard Veit]
+* 🐛 fix error handling. [Eduard Veit]
 
-  :recycle: do some shellcheck fixes
+* 🐛 fix sourcing of config file. [Eduard Veit]
+
+  ♻️ do some shellcheck fixes
 
 ### Documentation
 
-* :memo: document example of an docker-compose.yml file. [Eduard Veit]
+* 📝 document example of an docker-compose.yml file. [Eduard Veit]
 
-* :memo: document loop mode and dig as requirement. [Eduard Veit]
+* 📝 document `loop mode` and mention `dig` as requirement. [Eduard Veit]
 
-* :memo: update example of .env in README.md. [Eduard Veit]
+* 📝 update example of .env in README.md. [Eduard Veit]
 
-* :memo: add CHANGELOG.md. [Eduard Veit]
+* 📝 CHANGELOG.md. [Eduard Veit]
 
-* :memo: add example.env. [Eduard Veit]
+* 📝 add example.env. [Eduard Veit]
-
-* :memo: write README.md. [Eduard Veit]
-
-### Other
-
-* :recycle: refactor: rename environment variables. [Eduard Veit]
-
-* :recycle: refactor, fix and debug error handling. [Eduard Veit]
-
-* :recycle: refactor main code. [Eduard Veit]
-
-* Initial commit. [EV21]
 
 

Dockerfile

@@ -1,4 +1,4 @@
-FROM alpine:latest
+FROM alpine:3.16.4
 
 RUN \
 apk update \
@@ -7,7 +7,8 @@ apk add \
 bash \
 curl \
 jq \
-bind-tools
+bind-tools \
+tzdata
 
 WORKDIR /usr/src/app
 

README.md

@@ -7,8 +7,6 @@ IPv4 (A) and IPv6 (AAAA) record updates are supported.
 <!-- TOC -->
 
 - [✨ Update Methods](#-update-methods)
-  - [APIs](#apis)
-  - [DynDNS2](#dyndns2)
 - [📦 Requirements](#-requirements)
 - [🚀 Installation](#-installation)
 - [⚙ Configuration](#-configuration)
@@ -25,18 +23,16 @@ IPv4 (A) and IPv6 (AAAA) record updates are supported.
 
 The following update methods are currently implemented:
 
-### APIs
+| Provider            | API                   | TTL in seconds | Credentials                                                                                  | own domain via NS record                 | free (sub-) domain                   |
-
+|---------------------|-----------------------|----------------|----------------------------------------------------------------------------------------------|------------------------------------------|--------------------------------------|
-- INWX.com Domrobot JSON-RPC-API\
+| INWX.com            | Domrobot JSON-RPC-API | 300            | customer login `username` & `password`. Mobile TAN (OTP) is currently not supported by DynB. | ✔️ 🆓 for your registered domains @ inwx | ⛔ for your registered domains @ inwx |
-  Limitations:
+| INWX.com            | DynDNS2               | 60             | specific dyndns `username` & `password`                                                      | ✔️ 🆓 for your registered domains @ inwx | ⛔ for your registered domains @ inwx |
-  - minimum TTL is 300 (5 minutes)
+| deSEC.io (dedyn.io) | DynDNS2               | 60             | `token`                                                                                      | ✔️ 🆓                                    | ✔️                                   |
-
+| DuckDNS.org         | DynDNS2               | 60             | `token`                                                                                      | ⛔                                        | ✔️                                   |
-### DynDNS2
+| dynv6.com           | DynDNS2               | 60             | `token`                                                                                      | ✔️ 🆓                                    | ✔️                                   |
-
+| ddnss.de            | DynDNS2               | 10             | `update key` as `token`                                                                      | ⛔                                        | ✔️                                   |
-- INWX.com
+| IPv64.net           | DynDNS2               | 60             | `DynDNS Updatehash` as `token`                                                               | ✔️ 💲                                    | ✔️                                   |
-- deSEC.io (dedyn.io)
+| dynu.com            | DynDNS2               | 30             | `username` & `password`                                                                      | ✔️ 🆓                                    | ✔️                                   |
-- DuckDNS.org
-- dynv6.com
 
 ## 📦 Requirements
 
@@ -57,7 +53,7 @@ or simply clone this repo
 git clone https://github.com/EV21/dynb.git
 ```
 
-If you want to add the script to you PATH, run :point_down:
+If you want to add the script to you PATH, run 👇
 
 ```shell
 bash dynb.sh --link
@@ -79,7 +75,7 @@ DYNB_SERVICE_PROVIDER=inwx
 ## update method options: domrobot, dyndns
 DYNB_UPDATE_METHOD=domrobot
 
-## ip mode could be either: 4, 6 or dual for dualstack
+## ip mode could be either: 4, 6 or 64 for dualstack
 DYNB_IP_MODE=64
 
 ## If you are using the DomRobot RPC-API enter your credentials for the web interface login here
@@ -92,14 +88,14 @@ DYNB_TOKEN=
 
 ## 🏃 Run
 
-If you have a config file just run :point_down:
+If you have a config file just run 👇
 
 ```bash
 dynb
 ```
 
 Alternatively you can use parameters if your system meets the relevant requirements. This example shows the long form parameter, there are also short ones.\
-Call the help function :point_down:
+Call the help function 👇
 
 ```bash
 dynb --help
@@ -123,13 +119,13 @@ Just use the parameter `--interval 60` or the environment variable `DYNB_INTERVA
 
 ### crontab
 
-execute :point_down:
+execute 👇
 
 ```bash
 crontab -e
 ```
 
-then enter :point_down: to run dynb every five minutes.
+then add the following line 👇 to run dynb every five minutes.
 
 ```bash
 */5 * * * * $HOME/.local/bin/dynb >> $HOME/.local/share/dynb/dynb-cron.log
@@ -155,32 +151,40 @@ services:
     image: ev21/dynb
     container_name: dynb
     network_mode: host
-    build:
+    stdin_open: true
-      context: .
+    tty: true
-      dockerfile: ./Dockerfile
     environment:
       - DYNB_DYN_DOMAIN=dyndns.example.com
-      - DYNB_SERVICE_PROVIDER=inwx
+      # Providers: deSec, DuckDNS, dynv6, inwx, ddnss, ipv64
+      - DYNB_SERVICE_PROVIDER=desec
+      # Possible update methods are: dyndns, domrobot
       - DYNB_UPDATE_METHOD=dyndns
+      # IP modes: 4 (IPv4 only), 6 (IPv6 only), 64 both
       - DYNB_IP_MODE=64
+      # If your provider uses tokens use DYNB_TOKEN instead of DYNB_USERNAME and DYNB_PASSWORD
       - DYNB_USERNAME=User42
       - DYNB_PASSWORD=SuperSecretPassword
-      - DYNB_INTERVAL=60
+      # The interval in seconds is the time the script waits before executing it again
+      - DYNB_INTERVAL=300
+      # TZ: Timezone setting for correct log time
+      - TZ=Europe/Berlin
+      # TERM: For colorful console output (attached mode)
+      - TERM=xterm-256color
 ```
 
 ## environment variables
 
-| variable              | default value   | description                                                                                                    |
+| variable              | default value                                                                                                                  | description                                                                                                    |
-| --------------------- | --------------- | -------------------------------------------------------------------------------------------------------------- |
+|-----------------------|--------------------------------------------------------------------------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------|
-| DYNB_DYN_DOMAIN       | undefined       | required; `dyndns.example.com`                                                                                 |
+| DYNB_DYN_DOMAIN       | undefined                                                                                                                      | required; `dyndns.example.com`                                                                                 |
-| DYNB_SERVICE_PROVIDER | undefined       | required; `deSEC`, `duckdns`, `dynv6`, `inwx`                                                                  |
+| DYNB_SERVICE_PROVIDER | undefined                                                                                                                      | required; `deSEC`, `duckdns`, `dynv6`, `inwx`, `ddnss`, `ipv64`                                                |
-| DYNB_UPDATE_METHOD    | undefined       | required; `dyndns` or `domrobot` (with inwx)                                                                   |
+| DYNB_UPDATE_METHOD    | undefined                                                                                                                      | required; `dyndns` or `domrobot` (with inwx)                                                                   |
-| DYNB_IP_MODE          | undefined       | required; `4`, `6` or `64` for both                                                                            |
+| DYNB_IP_MODE          | undefined                                                                                                                      | required; `4`, `6` or `64` for both                                                                            |
-| DYNB_USERNAME         | undefined       | the requirement depends on your provider and the update method                                                 |
+| DYNB_USERNAME         | undefined                                                                                                                      | the requirement depends on your provider and the update method                                                 |
-| DYNB_PASSWORD         | undefined       | the requirement depends on your provider and the update method                                                 |
+| DYNB_PASSWORD         | undefined                                                                                                                      | the requirement depends on your provider and the update method                                                 |
-| DYNB_TOKEN            | undefined       | the requirement depends on your provider and the update method                                                 |
+| DYNB_TOKEN            | undefined                                                                                                                      | the requirement depends on your provider and the update method                                                 |
-| DYNB_INTERVAL         | undefined       | without this setting the script/docker container will run one time and exits                                   |
+| DYNB_INTERVAL         | undefined                                                                                                                      | without this setting the script/docker container will run one time and exits                                   |
-| DYNB_DEBUG            | undefined       | more console outputs                                                                                           |
+| DYNB_DEBUG            | undefined                                                                                                                      | more console outputs                                                                                           |
-| DYNB_IPv4_CHECK_SITE  | api64.ipify.org | You need a website or Web-API that outputs your remote IP                                                      |
+| DYNB_IPv4_CHECK_SITE  | tries in this order `ip64.ev21.de` (anonymous logging for 7 days), `api64.ipify.org`, `api.my-ip.io/ip`, `ip.anysrc.net/plain` | You need a website or Web-API that outputs your remote IP                                                      |
-| DYNB_IPv6_CHECK_SITE  | api64.ipify.org | You need a website or Web-API that outputs your remote IP                                                      |
+| DYNB_IPv6_CHECK_SITE  | tries in this order `ip64.ev21.de` (anonymous logging for 7 days), `api64.ipify.org`, `api.my-ip.io/ip`, `ip.anysrc.net/plain` | You need a website or Web-API that outputs your remote IP                                                      |
-| DYNB_DNS_CHECK_SERVER | undefined       | If you are using a local DNS Resolver/Server make sure it answers with the public answer or set another server |
+| DYNB_DNS_CHECK_SERVER | using the DynDNS2 providers DNS servers                                                                                        | If you are using a local DNS Resolver/Server make sure it answers with the public answer or set another server |

dynb.sh

@@ -12,67 +12,76 @@
 
 #DYNB_DYN_DOMAIN=
 
-## service provider could be deSEC, duckdns, dynv6, inwx
+# service provider could be deSEC, duckdns, dynv6, inwx
 #DYNB_SERVICE_PROVIDER=
 
 ## update method options: domrobot, dyndns
 #DYNB_UPDATE_METHOD=
 
-## ip mode could be either: 4, 6 or dual for dualstack
+# ip mode could be either: 4, 6 or dual for dualstack
 #DYNB_IP_MODE=
 
-## If you are using the DomRobot RPC-API enter your credentials for the web interface login here
+# If you are using the DomRobot RPC-API enter your credentials for the web interface login here
-## If you are using the DynDNS2 protocol enter your credentials here
+# If you are using the DynDNS2 protocol enter your credentials here
 #DYNB_USERNAME=
 #DYNB_PASSWORD=
-## or use a token
+# or use a token
 #DYNB_TOKEN=
 
-## TTL (time to live) for the DNS record
+# TTL (time to live) for the DNS record
-## This setting is only relevant for API based record updates (not DnyDNS2!)
+# This setting is only relevant for API based record updates (not DnyDNS2!)
-## minimum allowed TTL value by inwx is 300 (5 minutes)
+# minimum allowed TTL value by inwx is 300 (5 minutes)
 TTL=300
 
-## The IP-Check sites (some sites have different urls for v4 and v6)
+# The IP-Check sites (some sites have different urls for v4 and v6)
-## Pro tip: use your own ip check server for privacy
+# Pro tip: use your own ip check server for privacy
-## it could be as simple as that...
+# it could be as simple as that...
-## create an index.php with <?php echo $_SERVER'REMOTE_ADDR'; ?>
+# create an index.php with <?php echo $_SERVER'REMOTE_ADDR'; ?>
-_ipv4_checker=api64.ipify.org
+#DYNB_IPv4_CHECK_SITE=
-_ipv6_checker=api64.ipify.org
+#DYNB_IPv6_CHECK_SITE=
 
-## An exernal DNS check server prevents wrong info from local DNS servers/resolvers
+# An exernal DNS check server prevents wrong info from local DNS servers/resolvers
-_DNS_checkServer=
+#DYNB_DNS_CHECK_SERVER=9.9.9.9
 
-## if you are actively using multiple network interfaces you might want to specify this
+# if you are actively using multiple network interfaces you might want to specify this
-## normally the default value is okay
+# normally the default value is okay
 #_network_interface=eth0
 _network_interface=
 
 ######################################################
 ## You don't need to change the following variables ##
+
 _INWX_JSON_API_URL=https://api.domrobot.com/jsonrpc/
 _internet_connectivity_test_server=https://www.google.de
-_new_IPv4=
+_default_check_ip_servers=("ip64.ev21.de" "api64.ipify.org" "api.my-ip.io/ip" "ip.anysrc.net/plain")
-_new_IPv6=
+_ipv4_checker=
+_ipv6_checker=
+_DNS_checkServer=
+_remote_IPv4=
+_remote_IPv6=
 _dns_records=
 _main_domain=
 _is_IPv4_enabled=false
 _is_IPv6_enabled=false
 _interface_str=
-_status=
 _eventTime=0
 _errorCounter=0
 _response=
 _statusHostname=
 _statusUsername=
 _statusPassword=
-_version=0.3.0
+_version=0.5.3
 _userAgent="DynB/$_version github.com/EV21/dynb"
 _configFile=$HOME/.local/share/dynb/.env
 _statusFile=/tmp/dynb.status
-_debug=0
+_debug=false
 _minimum_looptime=60
-_loopMode=0
+_loopMode=false
+_remote_ip=
+_dns_ip=
+_has_remote_ip_error=
+_has_remote_ip4=false
+_has_remote_ip6=false
 
 # Ansi color code variables
 yellow_color="\e[0;33m"
@@ -103,9 +112,30 @@ function is_IPv6_address
   fi
 }
 
+## is_ip_address A B
+# parameters required
+# 1. param: ip_version
+# 2. param: ip_address
+function is_ip_address
+{
+  local ip_version=$1
+  local ip_address=$2
+  case $ip_version in
+    4)
+      is_IPv4_address "$ip_address"
+      result=$?
+    ;;
+    6)
+      is_IPv6_address "$ip_address"
+      result=$?
+    ;;
+  esac
+  return "$result"
+}
+
 function loopMode
 {
-  if [[ $_loopMode -eq 1 ]]
+  if [[ $_loopMode == "true" ]]
   then return 0
   else return 1
   fi
@@ -113,7 +143,7 @@ function loopMode
 
 function debugMode
 {
-  if [[ $_debug -eq 1 ]]
+  if [[ $_debug == "true" ]]
   then return 0
   else return 1
   fi
@@ -186,42 +216,145 @@ function fetchDNSRecords
   _dns_records=$(echo "$_response" | jq '.resData.record[]')
 }
 
+## getRecordID
 # requires parameter A or AAAA
 # result to stdout
 function getRecordID
 {
   echo "$_dns_records" |
-    jq "select(.type == \"${1}\") | .id"
+    jq --raw-output "select(.type == \"${1}\") | .id"
 }
 
-# requires parameter A or AAAA
+## do_dig_request A B
-# result to stdout
+# sets variable: _dns_ip
+#
+# requires parameter
+# 1. param: dns server address
+# 2. param: A or AAAA
+function do_dig_request
+{
+  local dns_server=$1
+  local record_type=$2
+  dig_response=$(dig @"$dns_server" in "$record_type" +short "$DYNB_DYN_DOMAIN" 2>&1)
+  dig_exitcode=$?
+  if [[ $dig_exitcode -gt 0 ]]
+  then
+    errorMessage "DNS request for $record_type @ $dns_server failed with exit code: $dig_exitcode $dig_response"
+    unset _dns_ip
+    return 1
+  else
+    case $record_type in
+    A) is_ip_address 4 "$dig_response"
+    ;;
+    AAAA) is_ip_address 6 "$dig_response"
+    ;;
+    esac
+    if test $? -gt 0
+    then
+      test -n "$dig_response" || debugMessage "dig response: $dig_response"
+      unset _dns_ip
+      return 1
+    fi
+  fi
+  # If the dns resolver lists multiple records in the answer section we filter the first line
+  # using short option "-n" and not "--lines" because of alpines limited BusyBox head command
+  _dns_ip=$(echo "$dig_response" | head -n 1)
+  return 0
+}
+
+## getDNSIP A
+# sets variable: _dns_ip
+#
+# requires parameter
+# 1. param: A or AAAA
 function getDNSIP() {
-  echo "$_dns_records" |
+  local record_type=$1
-    jq --raw-output "select(.type == \"${1}\") | .content"
+  if [[ $DYNB_UPDATE_METHOD == domrobot ]]
+  then
+    _dns_ip=$(echo "$_dns_records" |
+      jq --raw-output "select(.type == \"${record_type}\") | .content")
+  else
+    for current_dns_server in "${provider_dns_servers[@]}"
+    do
+      debugMessage "try dig DNS request with record type $record_type @$current_dns_server"
+      if do_dig_request "$current_dns_server" "$record_type"
+      then break
+      fi
+    done
+  fi
 }
 
+## getRemoteIP A
+# sets variable: _remote_ip,
+#
 # requires parameter
 # 1. param: 4 or 6 for ip version
-# 2. param: IP check server address
+#
 # result to stdout
 function getRemoteIP
 {
   local ip_version=$1
-  local ip_check_server=$2
+
-  if [[ -n $_DNS_checkServer ]]
+  if test -n "$_provider_check_ip"
-  then
+  then ip_check_servers=("$_provider_check_ip" "${_default_check_ip_servers[@]}")
-    curl --silent "$_interface_str" --user-agent "$_userAgent" \
-      --ipv"${ip_version}" --dns-servers "$_DNS_checkServer" --location "${ip_check_server}"
-  else
-    curl --silent "$_interface_str" --user-agent "$_userAgent" \
-      --ipv"${ip_version}" --location "${ip_check_server}"
-  fi
-  # shellcheck disable=2181
-  if [[ $? -gt 0 ]]; then
-    errorMessage "IPCheck (getRemoteIP ${1}) request failed"
-    exit 1
   fi
+  case $ip_version in
+    4)
+      if test -n "$_ipv4_checker"
+      then ip_check_servers=("$_ipv4_checker" "${_default_check_ip_servers[@]}")
+      else ip_check_servers=("${_default_check_ip_servers[@]}")
+      fi
+    ;;
+    6)
+      if test -n "$_ipv6_checker"
+      then ip_check_servers=("$_ipv6_checker" "${_default_check_ip_servers[@]}")
+      else ip_check_servers=("${_default_check_ip_servers[@]}")
+      fi
+    ;;
+  esac
+
+  for current_check_server in "${ip_check_servers[@]}"
+  do
+    debugMessage "try getting remote IPv$ip_version via $current_check_server"
+    response=$(curl --silent "$_interface_str" --user-agent "$_userAgent" \
+    --ipv"${ip_version}" --location "${current_check_server}")
+    curls_status_code=$?
+    # shellcheck disable=2181
+    if [[ $curls_status_code -gt 0 ]]
+    then
+      errorMessage "Remote IPv$ip_version request @ ${current_check_server} failed with curl status code: $curls_status_code"
+      _has_remote_ip_error=true
+      return_value=1
+    else
+      if is_ip_address "$ip_version" "$response"
+      then
+        _has_remote_ip_error=false
+        _remote_ip="$response"
+        return_value=0
+        break
+      else
+        errorMessage "The response from the IP check server $current_check_server is not an IPv$ip_version address: $response"
+        _has_remote_ip_error=true
+        return_value=1
+      fi
+    fi
+  done
+
+  case $ip_version in
+  4)
+    if [[ $_has_remote_ip_error == true ]]
+    then _has_remote_ip4=false
+    else _has_remote_ip4=true
+    fi
+  ;;
+  6)
+    if [[ $_has_remote_ip_error == true ]]
+    then export _has_remote_ip6=false
+    else export _has_remote_ip6=true
+    fi
+  ;;
+  esac
+  return "$return_value"
 }
 
 # requires parameter
@@ -232,12 +365,12 @@ function updateRecord
   if [[ ${ip_version} == 4 ]]
   then
     ID=$(getRecordID A)
-    IP=$_new_IPv4
+    IP=$_remote_IPv4
   fi
   if [[ ${ip_version} == 6 ]]
   then
     ID=$(getRecordID AAAA)
-    IP=$_new_IPv6
+    IP=$_remote_IPv6
   fi
   if [[ $IP != "" ]]
   then
@@ -263,102 +396,160 @@ function updateRecord
   fi
 }
 
-# using DynDNS2 protocol
+function prepare_request_parameters
-function dynupdate
 {
   # default parameter values
-  myip_str=myip
+  ipv4_parameter_name=myip
-  myipv6_str=myipv6
+  ipv6_parameter_name=myipv6
-
+  curl_parameters=("--user-agent" "$_userAgent")
-  INWX_DYNDNS_UPDATE_URL="https://dyndns.inwx.com/nic/update?"
-  DESEC_DYNDNS_UPDATE_URL="https://update.dedyn.io/?"
-  DUCKDNS_DYNDNS_UPDATE_URL="https://www.duckdns.org/update?domains=$DYNB_DYN_DOMAIN&token=$DYNB_TOKEN&"
-  DYNV6_DYNDNS_UPDATE_URL="https://dynv6.com/api/update?zone=$DYNB_DYN_DOMAIN&token=$DYNB_TOKEN&"
 
   case $DYNB_SERVICE_PROVIDER in
-    inwx* | INWX*)
+    [Ii][Nn][Ww][Xx]*)
-      dyndns_update_url=$INWX_DYNDNS_UPDATE_URL
+    # inwx.de
-      ;;
+    # in case of dualstack use you need to request both parameters with the same request
-    deSEC* | desec* | dedyn*)
+    # otherwise inwx will delete the not requested record type
-      dyndns_update_url="${DESEC_DYNDNS_UPDATE_URL}"
+      curl_parameters+=("--user" "$DYNB_USERNAME:$DYNB_PASSWORD")
-      ;;
+      curl_parameters+=("--get") # inwx will ignore the ipv6 parameter if you don't put it into the url
-    dynv6*)
+      dyndns_update_url="https://dyndns.inwx.com/nic/update"
-      dyndns_update_url="${DYNV6_DYNDNS_UPDATE_URL}"
+      provider_dns_servers=("ns.inwx.de" "ns2.inwx.de" "ns3.inwx.eu")
-      myip_str=ipv4
+    ;;
-      myipv6_str=ipv6
+    [Dd][Yy][Nn][Uu]*)
-      ;;
+      curl_parameters+=("--user" "$DYNB_USERNAME:$DYNB_PASSWORD")
-    DuckDNS* | duckdns*)
+      curl_parameters+=("--get")
-      dyndns_update_url="${DUCKDNS_DYNDNS_UPDATE_URL}"
+      dyndns_update_url="https://api.dynu.com/nic/update"
-      myip_str=ipv4
+      provider_dns_servers=("NS11.dynu.com" "NS10.dynu.com" "NS12.dynu.com")
-      myipv6_str=ipv6
+    ;;
-      ;;
+    [Dd][Ee][Ss][Ee][Cc]* | [Dd][Ee][Dd][Yy][Nn]* )
+    # deSEC.de / dedyn.io
+      curl_parameters+=("--header" "Authorization: Token $DYNB_TOKEN")
+      curl_parameters+=("--get")
+      curl_parameters+=("--data-urlencode" "hostname=$DYNB_DYN_DOMAIN")
+      dyndns_update_url="https://update.dedyn.io"
+      provider_dns_servers=("ns1.desec.io" "ns2.desec.org")
+      _provider_check_ip="https://checkip.dedyn.io" # checkipv4 and checkipv6 is also available
+    ;;
+    [Dd][Yy][Nn][Vv]6*)
+    # dynv6.com
+      ipv4_parameter_name=ipv4
+      ipv6_parameter_name=ipv6
+      curl_parameters+=("--get")
+      curl_parameters+=("--data-urlencode" "zone=$DYNB_DYN_DOMAIN")
+      curl_parameters+=("--data-urlencode" "token=$DYNB_TOKEN")
+      dyndns_update_url="https://dynv6.com/api/update"
+      provider_dns_servers=("ns1.dynv6.com" "ns2.dynv6.com" "ns3.dynv6.com")
+    ;;
+    [Dd][Uu][Cc][Kk][Dd][Nn][Ss]*)
+    # DuckDNS.org
+      ipv4_parameter_name=ip
+      ipv6_parameter_name=ipv6
+      curl_parameters+=("--get")
+      curl_parameters+=("--data-urlencode" "domains=$DYNB_DYN_DOMAIN")
+      curl_parameters+=("--data-urlencode" "token=$DYNB_TOKEN")
+      dyndns_update_url="https://www.duckdns.org/update"
+      provider_dns_servers=("ns1.duckdns.org" "ns2.duckdns.org")
+    ;;
+    [Dd][Dd][Nn][Ss][Ss]*)
+    # ddnss.de
+      ipv4_parameter_name=ip
+      ipv6_parameter_name=ip6
+      curl_parameters+=("--get")
+      curl_parameters+=("--data-urlencode" "host=$DYNB_DYN_DOMAIN")
+      curl_parameters+=("--data-urlencode" "key=$DYNB_TOKEN")
+      dyndns_update_url="https://ddnss.de/upd.php"
+      provider_dns_servers=("ns1.ddnss.de" "ns2.ddnss.de" "ns3.ddnss.de")
+    ;;
+    [Ii][Pp][Vv]64*)
+    # IPv64.net
+      ipv4_parameter_name=ip
+      ipv6_parameter_name=ip6
+      curl_parameters+=("--request" "POST")
+      curl_parameters+=("--header" "Authorization: Bearer $DYNB_TOKEN")
+      curl_parameters+=("--data-urlencode" "domain=$DYNB_DYN_DOMAIN")
+      dyndns_update_url="https://ipv64.net/nic/update"
+      provider_dns_servers=("ns1.IPv64.net" "ns2.IPv64.net")
+    ;;
     *)
       errorMessage "$DYNB_SERVICE_PROVIDER is not supported"
       exit 1
-      ;;
+    ;;
   esac
-
+  if test -n "$_DNS_checkServer"
-  # pre encode ip parameters
+  then provider_dns_servers=("$_DNS_checkServer" "${provider_dns_servers[@]}")
-  if [[ $_is_IPv4_enabled == true ]] && [[ $_is_IPv6_enabled == true ]]; then
-    dyndns_update_url="${dyndns_update_url}${myip_str}=${_new_IPv4}&${myipv6_str}=${_new_IPv6}"
   fi
-  if [[ $_is_IPv4_enabled == true ]] && [[ $_is_IPv6_enabled == false ]]; then
+}
-    dyndns_update_url="${dyndns_update_url}${myip_str}=${_new_IPv4}"
-  fi
-  if [[ $_is_IPv4_enabled == false ]] && [[ $_is_IPv6_enabled == true ]]; then
-    dyndns_update_url="${dyndns_update_url}${myipv6_str}=${_new_IPv6}"
-  fi
-  debugMessage "Update URL was: $dyndns_update_url"
 
-  ## request ##
+function prepare_ip_flag_parameters
-  case $DYNB_SERVICE_PROVIDER in
+{
-    inwx* | INWX*)
+  debugMessage "IPv4 enabled: $_is_IPv4_enabled; IPv6 enabled: $_is_IPv6_enabled; has remote IPv4: $_has_remote_ip4; has remote IPv6: $_has_remote_ip6"
-      _response=$(curl --silent "$_interface_str" \
+  if [[ $_is_IPv4_enabled == true ]] && [[ $_is_IPv6_enabled == true ]] && [[ $_has_remote_ip4 == true ]] && [[ $_has_remote_ip6 == true ]]
-        --user-agent "$_userAgent" \
+  then
-        --user "$DYNB_USERNAME":"$DYNB_PASSWORD" \
+    ip_flag_parameters=("--data-urlencode" "${ipv4_parameter_name}=${_remote_IPv4}" "--data-urlencode" "${ipv6_parameter_name}=${_remote_IPv6}")
-        "${dyndns_update_url}")
+  fi
-      ;;
+  if [[ $_is_IPv4_enabled == true ]] && [[ $_is_IPv6_enabled == false ]] || [[ $_is_IPv4_enabled == true ]] && [[ $_is_IPv6_enabled == true ]] && [[ $_has_remote_ip4 == true ]] && [[ $_has_remote_ip6 == false ]]
-    deSEC* | desec* | dedyn*)
+  then
-      _response=$(curl --silent "$_interface_str" \
+    ip_flag_parameters=("--data-urlencode" "${ipv4_parameter_name}=${_remote_IPv4}")
-        --user-agent "$_userAgent" \
+  fi
-        --header "Authorization: Token $DYNB_TOKEN" \
+  if [[ $_is_IPv4_enabled == false ]] && [[ $_is_IPv6_enabled == true ]] || [[ $_is_IPv4_enabled == true ]] && [[ $_is_IPv6_enabled == true ]] && [[ $_has_remote_ip4 == false ]] && [[ $_has_remote_ip6 == true ]]
-        --get --data-urlencode "hostname=$DYNB_DYN_DOMAIN" \
+  then
-        "${dyndns_update_url}")
+    ip_flag_parameters=("--data-urlencode" "${ipv6_parameter_name}=${_remote_IPv6}")
-      ;;
+  fi
-    dynv6* | duckDNS* | duckdns*)
+}
-      _response=$(
-        curl --silent "$_interface_str" \
-          --user-agent "$_userAgent" \
-          "${dyndns_update_url}"
-      )
-      ;;
-  esac
 
-  case $_response in
+function send_request
-    good* | OK* | "addresses updated")
+{
+  local _response
+  debugMessage "curl parameters: ${curl_parameters[*]} ${dyndns_update_url}"
+  _response=$(
+    curl --silent "$_interface_str" \
+    "${curl_parameters[@]}" \
+    "${dyndns_update_url}")
+  _curl_exit_code=$?
+  analyse_response
+  status_code=$?
+  return $status_code
+}
+
+function analyse_response
+{
+    case $_response in
+    good* | OK* | "addresses updated" | *Updated*hostname* | *'"info":"good"'*)
       if [[ $_response == "good 127.0.0.1" ]]; then
         errorMessage "$_response: Request ignored."
         return 1
       else
-        infoMessage "$_response: The DynDNS update has been executed."
+        infoMessage "The DynDNS update has been executed."
-        _errorCounter=0
+        debugMessage "Response: $_response"
         return 0
       fi
       ;;
-    nochg*)
+    *nochg*)
-      infoMessage "$_response: Nothing has changed, IP addresses are still up to date."
+      infoMessage "Nothing has changed, IP addresses are still up to date."
+      debugMessage "Response: $_response"
+      return 1
+      ;;
+    400* | *'Bad Request'*)
+      errorMessage "Bad Request."
+      debugMessage "Response: $_response"
+      return 1
+      ;;
+    *'Too Many Requests'*)
+      errorMessage "Too Many Request."
+      debugMessage "Response: $_response"
       return 1
       ;;
     abuse)
-      errorMessage "$_response: Username is blocked due to abuse."
+      errorMessage "Username is blocked due to abuse."
+      debugMessage "Response: $_response"
       return 1
       ;;
-    badauth | 401)
+    *badauth* | 401 | *Unauthorized*)
-      errorMessage "$_response: Invalid username password combination."
+      errorMessage "Invalid token or username password combination."
+      debugMessage "Response: $_response"
       return 1
       ;;
     badagent)
-      errorMessage "$_response: Client disabled. Something is very wrong!"
+      errorMessage "Client disabled. Something is very wrong!"
+      debugMessage "Response: $_response"
       return 1
       ;;
     !donator)
@@ -373,8 +564,9 @@ function dynupdate
       errorMessage "$_response: Hostname $DYNB_DYN_DOMAIN is invalid"
       return 1
       ;;
-    nohost)
+    *nohost*)
-      errorMessage "$_response: Hostname supplied does not exist under specified account, enter new login credentials before performing an additional request."
+      errorMessage "Hostname supplied does not exist under specified account, enter new login credentials before performing an additional request."
+      debugMessage "Response: $_response"
       return 1
       ;;
     numhost)
@@ -385,13 +577,17 @@ function dynupdate
       errorMessage "$_response: There is an internal error in the dyndns update system. Retry update no sooner than 30 minutes."
       return 1
       ;;
-    911 | 5*)
+    servererror | 911 | 5*)
       errorMessage "$_response: A fatal error on provider side such as a database outage. Retry update no sooner than 30 minutes."
       return 1
       ;;
     *)
-      if [[ "$_response" == "$_status" ]]; then
+      if test $_curl_exit_code -gt 0
-        errorMessage "An unknown response code has been received. $_response"
+      then
+        analyse_curl_exit_code $_curl_exit_code
+        return $?  
+      elif test -n "$_response" && [[ "$_response" == "$_previous_response_was" ]]; then
+        errorMessage "An unknown response code has been received: $_response"
         return 1
       else
         errorMessage "unknown respnse code: $_response"
@@ -401,19 +597,59 @@ function dynupdate
   esac
 }
 
+function analyse_curl_exit_code
+{
+  local current_curl_exit_code=$1
+  case $current_curl_exit_code in
+    6)
+      errorMessage "curl exit code: $_curl_exit_code; Couldn't resolve host: $dyndns_update_url"
+    ;;
+    7)
+      errorMessage "curl exit code: $_curl_exit_code; Failed to connect to host: $dyndns_update_url"
+    ;;
+    22)
+      errorMessage "curl exit code: $_curl_exit_code HTTP error code being 400 or above"
+    ;;
+    *)
+      errorMessage "curl exit code: $_curl_exit_code"
+    ;;
+  esac
+  return "$current_curl_exit_code"
+}
+
+# using DynDNS2 protocol
+function dynupdate
+{
+  prepare_ip_flag_parameters
+  curl_parameters+=("${ip_flag_parameters[@]}")
+  send_request
+  request_status=$?
+  return $request_status
+}
+
 function setStatus
 {
-  echo "_status=$1; _eventTime=$2; _errorCounter=$3; _statusHostname=$4; _statusUsername=$5; _statusPassword=$6" >/tmp/dynb.status
+  echo "_curl_exit_code_was=$1; _previous_response_was=$2 _eventTime=$3; _errorCounter=$4; _statusHostname=$5; _statusUsername=$6; _statusPassword=$7" >/tmp/dynb.status
 }
 
+declare _previous_response_was
+declare _curl_exit_code_was
+
 # handle errors from past update requests
 function checkStatus
 {
-  case $_status in
+  local check_string
-    nochg*)
+  if [[ -z "${_previous_response_was}" ]]
-      if [[ _errorCounter -gt 1 ]]; then
+  then check_string=$_curl_exit_code_was
+  else check_string=$_previous_response_was
+  fi
+  
+  case $check_string in
+    *nochg*)
+      if [[ _errorCounter -gt 1 ]]
+      then
         errorMessage "The update client was spamming unnecessary update requests, something might be wrong with your IP-Check site."
-        errorMessage "Fix your config an then delete $_statusFile or restart your docker container"
+        errorMessage "Fix your config and then delete $_statusFile or restart your docker container"
         return 1
       fi
       ;;
@@ -421,22 +657,21 @@ function checkStatus
       if [[ "$_statusHostname" == "$DYNB_DYN_DOMAIN" && ("$_statusUsername" == "$DYNB_USERNAME" || $_statusUsername == "$DYNB_TOKEN") ]]; then
         errorMessage "Hostname supplied does not exist under specified account, enter new login credentials before performing an additional request."
         return 1
-      else rm "$_statusFile"
+      else delete_status_file
       fi
       return 0
       ;;
-    badauth | 401)
+    *badauth* | 401 | *Unauthorized*)
-      if [[ "$_statusUsername" == "$DYNB_USERNAME" && "$_statusPassword" == "$DYNB_PASSWORD" ]]; then
+      if [[ "$_statusUsername" == "$DYNB_USERNAME" &&  ("$_statusPassword" == "$DYNB_PASSWORD" || $_statusPassword == "$DYNB_TOKEN") ]]; then
         errorMessage "Invalid username password combination."
         return 1
-      else rm "$_statusFile"
+      else delete_status_file
       fi
       return 0
       ;;
     badagent)
       errorMessage "Client is deactivated by provider."
-      echo "Fix your config and then manually remove $_statusFile to reset the client blockade."
+      echo "Please file an issue at GitHub or try another client :)"
-      echo "If it still fails file an issue at github or try another client :)"
       return 1
       ;;
     !donator)
@@ -451,94 +686,88 @@ function checkStatus
       echo "If it still fails file an issue at github or try another client :)"
       return 1
       ;;
-    911 | 5*)
+    servererror | 911 | 5* | *'Too Many Requests'*)
-      delta=$(($(date +%s) - _eventTime))
+      if check_delay 30
-      if [[ $delta -lt 1800 ]]
       then
-        errorMessage "$_status: The provider currently has an fatal error. DynB will wait for next update until 30 minutes have passed since last request, $(date --date=@$delta -u +%M) minutes already passed."
+        delete_status_file
+        return 0
+      else
+        errorMessage "$_previous_response_was: The provider currently has a fatal error."
         return 1
-      else rm "$_statusFile"
+      fi
+      ;;
+    *'Bad Request'*)
+      if [[ "$_statusUsername" == "$DYNB_USERNAME" &&  ("$_statusPassword" == "$DYNB_PASSWORD" || $_statusPassword == "$DYNB_TOKEN") ]]
+      then
+        errorMessage "Bad Request: Please check your credentials, maybe your token is invalid."
+        return 1
+      else delete_status_file
       fi
       return 0
       ;;
     *)
-      if [[ _errorCounter -gt 1 ]]
+      if [[ $_errorCounter -gt 1 ]] && [[ "$_curl_exit_code_was" -eq 0 ]]
       then
         errorMessage "An unknown response code has repeatedly been received. $_response"
         return 1
+      elif [[ $_errorCounter -gt 1 ]] && [[ "$_curl_exit_code_was" -eq 7 ]]
+      then
+        if check_delay 15
+        then
+          delete_status_file
+          return 0
+        else return 1
+        fi
       else return 0
       fi
       ;;
   esac
 }
 
+function check_delay
+{
+  local minutes=$1
+  local seconds=$(( minutes * 60 ))
+  delta=$(($(date +%s) - _eventTime))
+  if [[ $delta -lt $seconds ]]
+  then
+    errorMessage "DynB only executes an update when $minutes minutes have passed since the last failed request, $(date --date=@$delta -u +%M) minutes have already passed."
+    if loopMode
+    then sleep $seconds
+    else return 1
+    fi
+  else return 0
+  fi
+}
+
 # requires parameter
 # 1. param: 4 or 6 for IP version
 function ipHasChanged
 {
   local ip_version=$1
+  getRemoteIP "$ip_version"
+  if test $? -gt 0
+  then return 1
+  fi
   case ${ip_version} in
     4)
-      remote_ip=$(getRemoteIP 4 $_ipv4_checker)
+      getDNSIP A
-      if ! is_IPv4_address "$remote_ip"
+      _remote_IPv4=$_remote_ip
-      then
+      debugMessage "IPv4 from remote IP check server: $_remote_IPv4, IPv4 from DNS: $_dns_ip"
-        errorMessage "The response from the IP check server is not an IPv4 address: $remote_ip"
+    ;;
-        return 1
-      fi
-      if [[ $DYNB_UPDATE_METHOD == domrobot ]]
-      then dns_ip=$(getDNSIP A)
-      else
-        if [[ -n $_DNS_checkServer ]]
-        then dig_response=$(dig @"${_DNS_checkServer}" in a +short "$DYNB_DYN_DOMAIN")
-        else dig_response=$(dig in a +short "$DYNB_DYN_DOMAIN")
-        fi
-        if [[ $dig_response == ";; connection timed out; no servers could be reached" ]]
-        then
-          errorMessage "DNS request failed $dig_response"
-          return 1
-        fi
-        # If the dns resolver lists multiple records in the answer section we filter the first line
-        # using short option "-n" and not "--lines" because of alpines limited BusyBox head command
-        dns_ip=$(echo "$dig_response" | head -n 1)
-      fi
-      _new_IPv4=$remote_ip
-      debugMessage "IPv4 from remote IP check server: $_new_IPv4, IPv4 from DNS: $dns_ip"
-      ;;
     6)
-      remote_ip=$(getRemoteIP 6 $_ipv6_checker)
+      getDNSIP AAAA
-      if ! is_IPv6_address "$remote_ip"
+      _remote_IPv6=$_remote_ip
-      then
+      debugMessage "IPv6 from remote IP check server: $_remote_IPv6, IPv6 from DNS: $_dns_ip"
-        errorMessage "The response from the IP check server is not an IPv6 address: $remote_ip"
+    ;;
-        return 1
-      fi
-      if [[ $DYNB_UPDATE_METHOD == domrobot ]]
-      then dns_ip=$(getDNSIP AAAA)
-      else
-        if [[ -n $_DNS_checkServer ]]
-        then dig_response=$(dig @"${_DNS_checkServer}" in aaaa +short "$DYNB_DYN_DOMAIN")
-        else dig_response=$(dig in aaaa +short "$DYNB_DYN_DOMAIN")
-        fi
-        exitcode=$?
-        if [[ $exitcode -gt 0 ]]
-        then
-          errorMessage "DNS request failed with exit code: $exitcode $dig_response"
-          return 1
-        fi
-        # If the dns server lists multiple records in the answer section we filter the first line
-        dns_ip=$(echo "$dig_response" | head -n 1)
-      fi
-      _new_IPv6=$remote_ip
-      debugMessage "IPv6 from remote IP check server: $_new_IPv6, IPv4 from DNS: $dns_ip"
-      ;;
-    *) ;;
   esac
 
-  if [[ "$remote_ip" == "$dns_ip" ]]
+  if [[ "$_remote_ip" == "$_dns_ip" ]]
   then return 1
   else
     case ${ip_version} in
-    4) infoMessage "New IPv4: $_new_IPv4 old was: $dns_ip";;
+    4) infoMessage "Remote IPv4: $_remote_IPv4 DNS IPv4: $_dns_ip";;
-    6) infoMessage "New IPv6: $_new_IPv6 old was: $dns_ip";;
+    6) infoMessage "Remote IPv6: $_remote_IPv6 DNS IPv6: $_dns_ip";;
     esac
     return 0
   fi
@@ -559,8 +788,8 @@ function handleParameters
   then rm --verbose "$_statusFile"; exit 0
   fi
   # shellcheck disable=SC2154
-  if [[ $_arg_debug == "on" ]]
+  if [[ $_arg_debug == "on" ]] || [[ $DYNB_DEBUG == true ]]
-  then _debug=1
+  then _debug=true
   fi
   # shellcheck disable=SC2154
   if [[ $_arg_update_method != "" ]]
@@ -600,8 +829,8 @@ function handleParameters
   elif [[ $DYNB_INTERVAL -lt _minimum_looptime ]]
   then
     DYNB_INTERVAL=$_minimum_looptime
-    _loopMode=1
+    _loopMode=true
-  else _loopMode=1
+  else _loopMode=true
   fi
   if [[ $_network_interface != "" ]]
   then _interface_str="--interface $_network_interface"
@@ -619,9 +848,6 @@ function handleParameters
   then _is_IPv6_enabled=true
   fi
 
-  if [[ $DYNB_DEBUG == true ]]
-  then _debug=1
-  fi
   # shellcheck disable=SC2154
   if [[ -n $DYNB_IPv4_CHECK_SITE ]]
   then _ipv4_checker=$DYNB_IPv4_CHECK_SITE
@@ -671,8 +897,8 @@ function doUnsets
   unset _is_IPv4_enabled
   unset _is_IPv6_enabled
   unset _main_domain
-  unset _new_IPv4
+  unset _remote_IPv4
-  unset _new_IPv6
+  unset _remote_IPv6
   unset _version
   unset DYNB_DYN_DOMAIN
   unset DYNB_USERNAME
@@ -707,8 +933,25 @@ function doDomrobotUpdates
   fi
 }
 
+function delete_status_file
+{
+  if test -f "$_statusFile"
+  then
+    debugMessage "Delete status file with previous errors"
+    rm "$_statusFile"
+    unset _curl_exit_code_was
+    unset _previous_response_was
+    unset _eventTime
+    unset _errorCounter
+    unset _statusHostname
+    unset _statusUsername
+    unset _statusPassword
+  fi
+}
+
 function doDynDNS2Updates
 {
+  prepare_request_parameters
   changed=0
   if [[ $_is_IPv4_enabled == true ]] && ipHasChanged 4
   then ((changed += 1))
@@ -722,14 +965,16 @@ function doDynDNS2Updates
     then
       debugMessage "checkStatus has no errors, try update"
       if dynupdate
-      then debugMessage "DynDNS2 update success"
+      then
+        debugMessage "DynDNS2 update success"
+        delete_status_file
       else
         debugMessage "Save new status after dynupdate has failed"
-        setStatus "$_response" "$(date +%s)" $((_errorCounter += 1)) "$DYNB_DYN_DOMAIN" "${DYNB_USERNAME}" "${DYNB_PASSWORD}${DYNB_TOKEN}"
+        setStatus "$_curl_exit_code" "$_response" "$(date +%s)" $((_errorCounter += 1)) "$DYNB_DYN_DOMAIN" "${DYNB_USERNAME}" "${DYNB_PASSWORD}${DYNB_TOKEN}"
       fi
     else debugMessage "Skip DynDNS2 update, checkStatus fetched previous error."
     fi
-  else debugMessage "Skip DynDNS2 update, IPs are up to date or there is a connection problem"
+  else debugMessage "Skip DynDNS2 update"
   fi
 }
 
@@ -744,17 +989,20 @@ function doUpdates
 
 function ipv6_is_not_working
 {
-  curl --ipv6 --head --silent --max-time 5 $_internet_connectivity_test_server > /dev/null
+  execute_connectivity_check 6
-  status_code=$?
+  return $?
-  if test $status_code -gt 0
-  then return 0
-  else return 1
-  fi
 }
 
 function ipv4_is_not_working
 {
-  curl --ipv4 --head --silent --max-time 5 $_internet_connectivity_test_server > /dev/null
+  execute_connectivity_check 4
+  return $?
+}
+
+function execute_connectivity_check
+{
+  local ip_version=$1
+  curl --ipv"$ip_version" --head --silent --max-time 5 $_internet_connectivity_test_server > /dev/null
   status_code=$?
   if test $status_code -gt 0
   then return 0
@@ -782,11 +1030,8 @@ function check_internet_connection
   fi
 }
 
-function main
+function read_config_file
 {
-  # shellcheck disable=SC1091,SC1090
-  source "$(dirname "$(realpath "$0")")/dynb-parsing.sh"
-
   # shellcheck source=.env
   if test -f "$_configFile"
   then
@@ -800,6 +1045,15 @@ function main
       source "$alternativeConfig"
     fi
   fi
+}
+
+function main
+{
+  # shellcheck disable=SC1091,SC1090
+  source "$(dirname "$(realpath "$0")")/dynb-parsing.sh"
+
+  read_config_file
+
   if test -f "$_statusFile"
   then
     debugMessage "read previous status file"
@@ -817,7 +1071,8 @@ function main
     while : 
     do
       doUpdates
-      sleep $DYNB_INTERVAL
+      debugMessage "wait $DYNB_INTERVAL seconds until next check"
+      sleep "$DYNB_INTERVAL"
     done
   else doUpdates
   fi