xtables lock iptables pve-firewall problem?

[bugfish]

Hello there,

i got an error message i seem to unable to resolve myself:
sylux pve-firewall[1416]: status update error: iptables_restore_cmdlist: Another app is currently holding the xtables lock. Perhaps you want to use the -w option?

I found another thread here, where ip filtering should be disabled, and a bug report said that the bug has been fixed.
I deactivated IP Filtering for my VMs and ebtables, but the issue persists.

Maybe some ideas how to fix this?
My version is the "free" one i have no premium key or something

Thanks in advance, if you need any informations just let me know.
The system is dedicated to proxmox, there are no other services running, except one webmin installation (which should not conflict, as there are no firewall procedures set up there)

Bugfish

 

[bugfish]

By the way, it seems that the firewall is working well, just the reoccuring message in the logfile makes me thinking that something is not working properly.