Bonding Mode changes


Renowned Member
Apr 23, 2015
Hi ....
In the host, Setting up the network bonding in "active-backup" mode.
After creating a virtual machine, the bonding mode has changed to Balance-rr.
Does anyone know what causes the bonding mode changes from mode1 active-backup to mode0 Balance-rr.

Thank you for your help.
* Please post your '/etc/network/interfaces'
* please post the output of `ip -details addr`
* Please use code-tags for command output (especially with such long outputs it's hard to read).

* which version are you running (`pveversion -v`) - since usually pve5.x uses predictable network interface names (enpXsYfZ instead of eth0)?

eth0 seems down - not sure if this has something to do with the bond-mode switching over?

do you see anything related in `dmesg` or `journalctl -r` output?
I applogize for not using the code-tags.
for simple reading to debug the interface names are changed to eth0 and eth1. But in the actual interface file there are eno1 and eno2.
proxmox-ve: 5.2-2 (running kernel: 4.15.17-1-pve)

the eth0 status down is normal, since the bond mode has changed to balance-rr.

I am going through the long lines of `dmesg` or `journalctl -r` will let you know.
Any specifics you want me to look at.

Thank YOU!
I appreciate your help.
the eth0 status down is normal, since the bond mode has changed to balance-rr.
* I would expect that both interfaces are used in a balance-rr situation - also the interface seems not connected (NO-CARRIER flag in ip a output)
* make sure that both interfaces are up and there are no errors there


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