Bug #6227


LAGG MTU not set correctly when it has child QinQ interfaces

Added by Chris Rowe almost 8 years ago. Updated about 7 years ago.

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Issue number 2786 ( describes an issue where the MTU on the parent interfaces of a LAGG or VLAN were not being set correctly. This was resolved for the most part, but the solution didn't apply correctly for an instance where you have a QinQ on top of a LAGG. The MTU of the QinQ interfaces is not being read and hence the MTU of the parent interfaces and LAGG as a whole default to 1500.

I've managed to use the changes made in that bug to, for the most part, resolve this. Apologies, I'm not a programmer and don't have a clue how to create a diff or pull request. So for the moment will just upload the entire that I have modified.

The changes I've made will check for any child QinQs on a LAGG, check their MTU values and set the LAGG MTU accordingly. Ideally, this would be modified slightly, so that if there are Child QinQs and no MTU has been explicitly set on them, the LAGG is set to 1504 to allow for the additional header overhead of the QinQ. I might take a look at doing this later.

Files (172 KB) Chris Rowe, 04/21/2016 02:01 PM (1.92 KB) Chris Rowe, 04/22/2016 03:16 AM
Actions #1

Updated by Chris Rowe almost 8 years ago

Figured out how to make a diff file of the changes, attached.

Actions #3

Updated by Luiz Souza over 7 years ago

  • Assignee set to Luiz Souza
Actions #4

Updated by Chris Buechler over 7 years ago

  • Status changed from New to Confirmed
  • Target version set to 2.3.2
  • Affected Version changed from 2.3 to 2.3.x

that PR seems fine to merge. Luiz, please review and merge if agreed.

Actions #5

Updated by Chris Buechler over 7 years ago

  • Target version changed from 2.3.2 to 2.4.0
Actions #6

Updated by Chris Buechler over 7 years ago

  • Status changed from Confirmed to Feedback

PR merged

Actions #7

Updated by Jim Pingle about 7 years ago

  • Status changed from Feedback to Resolved
  • Target version changed from 2.4.0 to 2.3.3

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