Comment 10 for bug 1910209

Christian, thank you so much, the below solution works for me.

$ sudo systemctl edit ovsdb-server.service
[Service]
RuntimeDirectoryPreserve=yes

BTW, only one way to change vhostuser path is using ovs other_config:vhost-sock-dir, but it is a subdir under /var/run/openvswitch, so it can't fix this.

https://github.com/openvswitch/ovs/blob/master/lib/dpdk.c#L360.

If you create dpdkvhostuserclient port by yourself and add-port it by yourself, you can specify full path, but for me, these are handled by openstack, so I can't control this, other_config:vhost-sock-dir is only one way to change this, but it is relative path, it can't be beyond /var/run/openvswitch.