DNS configuration for the SmartOS slaves

[joaocgreis]

As seen recently in nodejs/node-v0.x-archive#25858 , DNS configuration is sensitive for the tests. The test machines should be configured to use Google DNS servers, and using other servers may cause tests to fail, as discussed in nodejs/node-v0.x-archive#8056 .

I changed the DNS configuration in the SmartOS slaves by editing /etc/resolv.conf. I am now looking for a way to make this permanent and documented.

I have very little experience with SmartOS, by my research it seems the proper place to change the DNS configuration in SmartOS is in the zone (VM) configuration: https://wiki.smartos.org/display/DOC/How+to+create+a+zone+%28+OS+virtualized+machine+%29+in+SmartOS . Can we access this configuration?

Another way would be to add the servers to /etc/resolv.conf in the ansible script, with something like (untested):

    - name: Remove 4.2.2.2 from the list of DNS servers
      lineinfile: dest=/etc/resolv.conf state=absent regexp='^(\s*)nameserver(\s+)4.2.2.2(\s*)$'
      tags: general

    - name: Add 8.8.8.8 to the list of DNS servers
      lineinfile: dest=/etc/resolv.conf state=present regexp='^(\s*)nameserver(\s+)8.8.8.8(\s*)$' line='nameserver 8.8.8.8'
      tags: general

    - name: Add 8.8.4.4 to the list of DNS servers
      lineinfile: dest=/etc/resolv.conf state=present regexp='^(\s*)nameserver(\s+)8.8.4.4(\s*)$' line='nameserver 8.8.4.4'
      tags: general

However, I don't know if/when this gets overwritten.

So, should I test the ansibles changes above carefully and open a PR, can we access the zone configuration or should this be done in some other way?

[chorrell]

If this is a machine on the Joyent Public Cloud you would not be able to modify the zone configuration. However, /etc/resolv.conf should only be populated at provision time so any modifications you make should persist after a reboot. Also note that depending on which data center you provision to I think the 4.2.2.2 entry might not always be added. I'm not 100% on that though. It's probably easier to just ensure you have the Google DNS servers and no other entries.

[joaocgreis]

@chorrell that's what I needed to know, thank you! PR it is then.

[joaocgreis]

Fixed by 18b3608.