IP address changed but relation data (hostname and private-address) still not updated

Or maybe this is juju that updates hostname and private-address?

This is juju 2.6.10.

As discussed with Ian (wallyworld):

|14:34 <wallyworld_> hloeung: if i recall, private-address is set when the relation is first set up. it's use is deprecated
in favour of using network-get. i wonder what that shows. typically i think an address chnage on a host machine generates a
config-change hook and from there you can get any new address values via unit-get private-address, but network-get is
preferred

network-get provides the correct info:

| ubuntu@ip-10-127-251-15:~$ sudo juju-run ubuntu-repository-cache/2 "network-get website"
| bind-addresses:
| - macaddress: ""
| interfacename: ""
| addresses:
| - hostname: ""
| address: 10.127.251.15
| cidr: ""
| egress-subnets:
| - 10.127.251.15/32
| ingress-addresses:
| - 10.127.251.15

So the HAProxy charm should use network-get rather than private-address.

Used relation-set to work around it for now:

| sudo juju-run ubuntu-repository-cache/2 "relation-set -r website:4 hostname=10.127.251.15 private-address=10.127.251.15"

u-r-c also uses relation-get private-address for it's peers and the metadatasync.

You can use ingress-address which replaced private-address - it is populated by Juju when a unit enters the relation scope at the Juju level - in other words, on <name>-relation-joined an ingress-address for a remote unit will be present.

`network-get <binding-name>` can be used to retrieve ingress-address and bind-address of the unit for the current hook execution.

As for hostnames, see https://bugs.launchpad.net/juju/+bug/1864086 for more info.

Yeah, ingress-address (via network-get) is what we want the charms to be using as that's what juju keeps up-to-date rather than 'relation-get private-address' which is only changed on establishing the relation.