create bridge on-demand

[hellt]

When link' kind is set to bridge and the bridge does not exist - create the bridge automatically with the tcp offload set to off and default MTU set to 9212

[karimra]

This complicates a few things like deleting the bridge or not on destroy.
The bridge idea is meant to be used to connect different fabrics together, so it can belong to multiple fabrics.

So a few decisions need be made when implementing this:

• delete the bridge or just the iterface on destroy, can be controlled via a flag
• add a few config options under a bridge dut like mtu or rely on default values... Might be incompatible when the bridge is used by multiple fabrics.

[hellt]

The bridge can be deleted only if it has no interfaces attached to it, so I think its ok to keep the flow as follows: 1. create the bridge if its not created already upon the lab deployment 2. delete the bridge on destroy if no interfaces are connected (interfaces got deleted first)

…

On Wed, Oct 7, 2020 at 12:04 PM Karim Radhouani ***@***.***> wrote: This complicates a few things like deleting the bridge or not on destroy. The bridge idea is meant to be used to connect different fabrics together, so it can belong to multiple fabrics. So a few decisions need be made when implementing this: - delete the bridge or just the iterface on destroy, can be controlled via a flag - add a few config options under a bridge dut like mtu or rely on default values... Might be incompatible when the bridge is used by multiple fabrics. — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#84 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ABLKV5NNN4FDF5OJ6XBG4XDSJQ4MLANCNFSM4SHFGRUA> .

[karimra]

In this case we need to make sure that changes like mtu and offloading are not applied to already existing bridges

[hellt]

Dup of #2267