[2.x] MAAS not adding mtu size change to dhcpd.conf

[Jeff Hillman]

When editing the MTU size for a VLAN and DHCP is enabled on that VLAN, MAAS is not adding the line

option interface-mtu <mtu size>;

to that VLAN.

Using a DHCP snippit is a work around for this, but MAAs should be performing this action when that value is changed.

In my case, I had enabled DHCP, then later altered the MTU size. I have not tested in the reverse order.

This entire issue was causing PXE to fail.

[Christian Reis (kiko)]

Escalating to high (has unobvious workaround)

[Jeff Hillman (jhillman)]

My apologies for this omission on the initial report.

maas 2.2.2-6099-g8751f91-0ubuntu1 on Xenial

[Andres Rodriguez (andreserl)]

As per the bug report from Jeff:

"Using a DHCP snippit is a work around for this"

This combined with the fact that MAAS has a feature that allows to perform custom configuration for DHCP, tells me that the work around is very obvious and very easy to perform.

Kiko, do you disagree?

[Christian Reis (kiko)]

By unobvious I meant that the path from seeing the symptom to deciding where the problem is and how to fix is not obvious.

In more detail: Jeff, Ante and I had to spend hours debugging the issue to find out the root cause -- MTU issues are just a pain and we shouldn't let people fall into this trap. So I'd keep it at High.

[Dean Henrichsmeyer (dean)]

I agree the bug priority should stay high but it doesn't need to be covered under the field high SLA. It doesn't match the criteria.

[Mike Pontillo (mpontillo)]

Hm, for some reason the merge proposal for this didn't get linked. This landed in MAAS 2.4.

https://code.launchpad.net/~mpontillo/maas/+git/maas/+merge/337408