private-address returns name, not ip

Charms will retrieve this value from relations (relation-get private-address) and may fail when they are handed a name rather than an IP address (arbitrary depending on provider). This can't be worked around in charm helpers

Stuart,

This is working locally for me on juju 2.0 (ie I can run "juju run --unit=<unitname>/0 'unit-get private-address'" for charms in my deployment and it returns an ip. Can you please re-open with exact recreate steps if this is still an issue for you.

Thanks!

This is a known issue with the Juju tooling around networking. We are working to enable specific tools for address vs hostname. It'll all be pulled into the network get functionality and you'll be able to get just the hostname or just the IP address. That work though won't be completed until Juju 2.1.

This bug was opened for 1.25.4, which I found had changed behaviour from 1.25.3 with certain providers. It hasn't broken under 2.0 yet afaik.

I'm setting this to wishlist for 'juju'. While the behavior isn't broken at the moment, it is already targeted to 2.1.0 and having things documented as returning an IP address rather than a name is what is required here. So providers can't return rubbish and claim 'works as designed'. If not wishlist, it is invalid.

I have also added a documentation issue https://github.com/juju/docs/issues/1409 to clarify private-address behavior and return value.

@Stuart,
I think that the only provider that exhibited this behavior was MAAS. Because there were considerable differences between MAAS 1.9 and 2.0, I am guessing that you are not seeing this behavior with Juju 2.0 is because you are running against MAAS 2.0.
Could you please clarify which provider, including versions, was causing you issues?

I suspect that the docs and Juju are correct in saying that we expected an IP to be returned as private-address value. So there may not be anything to do here.

This still happens under 2.1.1 with the manual provider. I have production installations where monitoring is failing because the charm is receiving a DNS name instead of an address from 'unit-get private-address'. Confirmed with 'juju run --unit foo/0 'unit-get private-address'

PostgreSQL lag monitoring is failing in the telegraf charm. The database query is failing because hostname is being send instead of a valid IP address.

The PostgreSQL charm is failing, similarly to telegraf, in that queries to the pg_stat_replication table require an IP address and we are attempting to use a DNS name.

With modern juju, network-get will return actual addresses for the addresses.