HA pool rebalancing
This idea is not new. It was recently brought up by @cathya in Porto (see notes. The overall concept is to design and implement a mechanism similar to the one in ISC DHCP. When there are two servers in load-balancing, it is possible that one of them will run out of addresses while the other one still has many.
Couple random comments:
- The pool rebalancing would somehow make both partners negotiate the pools and rebalance them.
- Using a hysteresis approach with high/low threshold would prevent the mechanism to go crazy when running out of addresses. We don't want it to go crazy when there's one or two addresses left.
- The pool dynamism would add extra complexity as the modified pool range would need to be stored somewhere that would survive crashes/reboots etc.
This requires a design. It's a complicated feature request with a high potential for endless tweaks, conflicting tuning requests etc.
We will do it one day, but this would require a lot of design, testing and tuning.