In each datacenter we have 4 mw* servers which act as mcrouter proxies, and 4 more that act as scap proxies. I was wondering if it makes sense to use the same set of 4 servers for both, in order to have 4 snowflakes in each DC instead of 8. Further more, we could consider if it makes sense to have dedicated VMs to specifically serve this roles and decouple them from mediawiki roles.
The problem I see (and have came across), is that we, generally, consider mw* servers as expendables, but there are those 8 servers that are we should keep in mind when e.g. reimaging or decommissioning.