Depooling servers

Contains various ways to depool different servers. In a glorious future, we'd just need to do conftool depool <service> <node> but we aren't there yet!

cp*** machines

These are the varnish frontends, and should be depooled via conftool. To fully depool a server, do as root on any puppetmaster frontend:

confctl select dc=<dc>,cluster=<cluster-name>,name=cp*** set/pooled=no

You can find out <cluster-name> from looking at conftool-data/nodes/ in the operations/puppet repository.

An easier option is to ssh into the server and just run

$ sudo -i depool

To re-pool, run:

$ sudo -i pool

Note the use of sudo -i. depool needs environment variables to get access to etcd.

mw* machines (and others)

The mw* application servers and other servers managed via pybal/etcd are depooled by using conftool. This is documented at https://wikitech.wikimedia.org/wiki/LVS#Etcd_as_a_backend_to_Pybal_.28All_of_production.29