Shared-cache update peer-list in k8s

[edgsantos]

Going through the hitch repo I noticed that hitch has support for shared-cache
Problem being, from my understanding if i have a 3 POD setup, each hitch container must know the IP of the remaining PODs to fill the shared-cache-peer list.

Any guidance on how this could be done in kubernetes?
In a VM setup it would be relatively easy to change the configuration upon a change using Puppet or Chef. Using a more dynamic setup like kubernetes i'm struggling to find a proper way to keep the peer list updated?

Thanks

[gquintard]

Hi,

There are a couple of facets to that (interesting) question:

• we don't currently enable this in our packages, so you would have to build your own
• at the moment, we don't reload the IP lists, so that is moderately useful if you want to clamp down the peers to the exactly the k8s population
• you could use an operator or something like discovery (not open-source though) to list an reload, once it's supported
• that being said, given that there appears to be multicast support (I haven't tested it), does it matter that you can't precisely list all the pods?

[edgsantos]

that being said, given that there appears to be multicast support (I haven't tested it), does it matter that you can't precisely list all the pods?

Multicast works and seems a way better alternative than keeping lists of IPs 👍
@gquintard are you able to point me to some documentation / code that talks about multicast support?

[gquintard]

I really only looked #115 (comment) which seems straightforward, but there may be dragons