Host network bridge and kvm/libvirtd/qemu problems

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Re: Host network bridge and kvm/libvirtd/qemu problems

Post by jlehtone » 2021/02/02 19:28:34

beargfr wrote:
2021/02/01 22:44:43
apparently "brctl" has been deprecated/dropped in favor of "ip", part of the iproute2 package, but good luck on finding any kind of documentation that tells you things like "if you did it this way using brctl, then here's how you do the same thing using ip".
Websearch for "ip bridge vs brctl" yields: ... mands.html
That is not new, but it does list some cases.

However, when using NetworkManager one does not call "bridge" nor "brctl" directly (except to query information).
If one replaces NetworkManager with network.service, one still does not call them directly but writes appropriate config files.

I have to reiterate, if you truly do have bridged network topology, then the firewall should never see any bridged traffic whether you set rules with firewall-cmd, iptables, or nft. Firewall has effect only if you explicitly enable filtering for bridged traffic.

You wrote that system did function until recently. I presume you did not change config.
Did you install updates (which is the right thing to do)?
Update of, say firewalld, could explain some changes in ruleset but not to the extent that bridged traffic would be filtered (since that has never been done by default on RHL/RHEL/CentOS systems).

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