[Labs-l] Reminder: dns changes this week

[Andrew Bogott]

On 6/1/15 5:39 PM, Andrew Bogott wrote:
> The slow march to update labs dns will hit a few milestones this 
> week.  If all goes well, labs users won't notice anything at all. If 
> we run into trouble there may be brief outages; if you notice an 
> outage please notify me immediately.
>
> 2015-06-02:  Starting tomorrow, new instances will use the new dns 
> system by default.
>
> 2015-06-02 through -05:  During the week, Yuvi will be moving a few 
> critical hosts (proxies, mostly) over to the new system.
>
> 2015-06-09:  On Monday I'll switch remaining instances to the new system.

I'm doing this right now.  Please let me know if you encounter strange 
behavior.


>
> If you have an instance using self-hosted puppet, today is a good day 
> to rebase your puppet code so that you're set up to cope with these 
> changes.  Honestly, every day is a good day to rebase your puppet code :)
>
>
> Details, for the technically interested:
>
> During each of the above steps, sets of instances will be moved over 
> to using a new dns server.  That server is named 
> 'labs-recursor0.wikimedia.org' and uses pdns-recursor. Pdns-recursor 
> is backed in turn by a pdns implementation running on the same 
> server.  The records in pdns are populated via openstack 
> designate-sink, a tool which hooks instance creation and creates an A 
> record.
>
> Use of the old (dnsmasq) system is maintained via the puppet setting 
> 'use_dnsmasq'.  So when I say I'm 'moving' an instance, in reality I'm 
> just removing the use_dnsmasq flag.
>
> The new system supports old-school names (name.eqiad.wmflabs) as well 
> as project-qualified names (name.projectname.eqiad.wmflabs) and also 
> supports rudimentary reverse lookups.
>