[SOLVED] One node found to have revert MTU to default 1500

stefws

Member
Jan 29, 2015
302
4
18
Denmark
siimnet.dk
This morning I found that one of our hypervisor nodes was revert an openvswitch 2.3.2-1 to default mtu of 1500 instead of the configured 9000. Underlying NIC still had 9000 for their MTUs, but the openvswitch vmbr1 only had 1500 and I couldn't configure it from CLI with: ifconfig vmbr1 mtu 9000, it stayed at 1500, had to reboot the node to get it back to 9000.

Anyone see similar or know of a possible RC for such?
 
This morning I found that one of our hypervisor nodes was revert an openvswitch 2.3.2-1 to default mtu of 1500 instead of the configured 9000. U

afaik the version included with the proxmox no-subscription repos is :
openvswitch-switch: 2.3.2-2 (not sure about enterprise repo version)

Any chance this is the host that had a reverted subscription key https://forum.proxmox.com/threads/one-node-failed-to-obtain-its-subscription.25442/ ?
In that case it can not grab the openvswitch package from the pve-enterprise repository and grabs it from whatever repositories are present (ie debian ) and have it.

else i'd check that the repositories are set correctly:
https://pve.proxmox.com/wiki/Package_repositories

if that is not the issue check your mtu settings via
nano /etc/network/interfaces
and
compare https://pve.proxmox.com/wiki/Open_vSwitch#Note_on_MTU




We've only ever had issues with MTU reversion when a wrong version was upgraded from a wrong repo by mistake.

ps.: you know about this right ?
The network configuration is usually changed using the web interface. Changes are stored to /etc/network/interfaces.new, and are activated when you reboot the host. Actual configuration resides in /etc/network/interfaces.
You can just do
/etc/init.d/networking restart

fixes most issues
 
Last edited:
afaik the version included with the proxmox no-subscription repos is :
openvswitch-switch: 2.3.2-2 (not sure about enterprise repo version)

if that is not the issue check your mtu settings via
nano /etc/network/interfaces
and
compare https://pve.proxmox.com/wiki/Open_vSwitch#Note_on_MTU

We've only ever had issues with MTU reversion when a wrong version was upgraded from a wrong repo by mistake.

ps.: you know about this right ?

You can just do
/etc/init.d/networking restart

fixes most issues
My mistake it is v.2.3.2-2 ;) and network config was/is okay, never set net config from GUI only manually. Reboot fixed issue.
Yes this was the node that seem to have lost it's subscription key, but now that's also fixed. Hopefully this wont happen again...
 

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