Resolve error 'the working directory is not writable' by switching into the /tmp/bind directory before executing the bind process

README.md

@@ -1,6 +1,6 @@
-### ISC BIND9 Container (Stable: 9.14.8_xx) built on top of Alpine
-### Last update: 2-6-20
-### Latest Stable Docker Tag: 9.14.8-r0
+### ISC BIND9 Container (Stable: 9.16.6_xx) built on top of Alpine
+### Last update: 8-31-20
+### Latest Stable Docker Tag: 9.16.6-r0
 
 NOTE: "Last Update" is the date of the latest DockerHub build.
 
@@ -154,6 +154,20 @@ logging {
     category default  { stdout; };
 };
 
+For more information, see: https://www.slideshare.net/MenandMice/bind-9-logging-best-practices
+
+## How do I just change Bind STDERR to STDOUT logging?
+
+There is now a "BIND_LOG" ENV (environment) variable for logging
+
+Environment variables can both have a default and be customized at run time. 
+
+```
+"-g" = (default) Run the server in the foreground and force all logging stderr.
+"-f" = Run the server in the foreground
 ```
 
-For more information, see: https://www.slideshare.net/MenandMice/bind-9-logging-best-practices
+By default, the "-g" value is set, as that logs all to STDERR.
+You can now override it with "-f" by passing `-e "BIND_LOG=-f"` to `docker run`
+
+

container/Dockerfile

@@ -3,6 +3,11 @@ EXPOSE 53 53/udp
 
 RUN apk --update upgrade && apk add bind bind-tools bind-plugins
 
+# BIND Log Options - you can override at run time
+# "-g" = (default) Run the server in the foreground and force all logging stderr.
+# "-f" = Run the server in the foreground
+env BIND_LOG -g
+
 # /etc/bind needs to be owned by root, group owned by "bind", and chmod 750
 # since we are mounting, do it manually
 # NOTE: Per Dockerfile manual --> need to mkdir the mounted dir to chown
@@ -12,7 +17,7 @@ RUN apk --update upgrade && apk add bind bind-tools bind-plugins
 # NOTE: Per Dockerfile manual --> need to mkdir the mounted dir to chown
 # &
 # Get latest bind.keys
-RUN mkdir -m 0770 -p /etc/bind && chown -R root:named /etc/bind ; \
+RUN mkdir -m 0750 -p /etc/bind && chown -R root:named /etc/bind ; \
     mkdir -m 0770 -p /var/cache/bind && chown -R named:named /var/cache/bind ; \
     wget -q -O /etc/bind/bind.keys https://ftp.isc.org/isc/bind9/keys/9.11/bind.keys.v9_11 ; \
     rndc-confgen -a

container/configs/default-zones/db.root

@@ -9,8 +9,8 @@
 ;           on server           FTP.INTERNIC.NET
 ;       -OR-                    RS.INTERNIC.NET
 ; 
-;       last update:     January 30, 2018 
-;       related version of root zone:     2018013001
+;       last update:     April 29, 2020 
+;       related version of root zone:     2020042901
 ; 
 ; FORMERLY NS.INTERNIC.NET 
 ;

container/entrypoint.sh

@@ -1,8 +1,14 @@
 #!/bin/sh
 OPTIONS=$@
+# "Run Time" changes - needed for when creating a *new* directory/first-time volume map
+# A great example of this is "/var/cache/bind" for dynamic configs, and mapping it in
+# The first time around, it will not be owned by named:named, and thus it won't be writable
+mkdir /tmp/bind
 chown -R root:named /etc/bind /var/run/named
-chown -R named:named /var/cache/bind
-chmod -R 770 /var/cache/bind /var/run/named
-chmod -R 750 /etc/bind
-# Run in foreground and log to STDERR (console):
-exec /usr/sbin/named -c /etc/bind/named.conf -g -u named $OPTIONS
+chown -R named:named /var/cache/bind /tmp/bind
+chmod -R 770 /etc/bind /var/cache/bind /var/run/named
+find /etc/bind /var/cache/bind -type f -exec chmod 640 -- {} +
+# By default - run in foreground and log to STDERR (console)
+# can be changed by running container with: -e "BIND_LOG=-f"
+cd /tmp/bind
+exec /usr/sbin/named -c /etc/bind/named.conf $BIND_LOG -u named $OPTIONS