On 15/3/2021 9:11 μ.μ., Aki Tuomi wrote:
On 15/03/2021 20:54 Paterakis E. Ioannis <j...@uoc.gr> wrote:
On 15/3/2021 6:09 μ.μ., Steven Varco wrote:
Hi John
Thanks for you input.
So you basically state that („physically“) separating the director servers from
keepalive/haproxy servers is the only option?
I would like to avoid setting up two additional machines for that whenever
possible, as any node more in the chain potentially is another point of
failure… ;)
Nope, it's not the only option. You can always have all three daemons
(keepalived/haproxy/director) on each machine. Keepalived will handle
the floating ip job, haproxies will have no problems with the floating
ip, the directors will always be binded to the static ips of the
machines and have their setup in the haproxies. That's all.
But, if you plan to make a Highly available environment, u have to
consider splitting your services to different VMs, and them to different
hypervisors in order to be as Highly available as you can....
John
The point of dovecot director is that it acts as a proxy that always routes
users to same backend. You can use keepalived, if it supports external
commands, to maybe tell director which backends are up / down.
It's not keepalived's work to tell the directors which backend is
up/down. You can use poolmon for that. keepalived will make sure the
floating ip will always be assigned on an alive haproxy. Then it's
haproxies' work to check the aliveness of directors. Then It's Directors
job to assign the users to the same dovecot backend all the time, and so
on....
Don't mix things.
J
