On Mon, Nov 27, 2023 at 11:49:16AM +0000, Felix Huettner wrote: > conntrack zones are heavily used by tools like openvswitch to run > multiple virtual "routers" on a single machine. In this context each > conntrack zone matches to a single router, thereby preventing > overlapping IPs from becoming issues. > In these systems it is common to operate on all conntrack entries of a > given zone, e.g. to delete them when a router is deleted. Previously this > required these tools to dump the full conntrack table and filter out the > relevant entries in userspace potentially causing performance issues. > > To do this we reuse the existing CTA_ZONE attribute. This was previous > parsed but not used during dump and flush requests. Now if CTA_ZONE is > set we filter these operations based on the provided zone. > However this means that users that previously passed CTA_ZONE will > experience a difference in functionality. > > Alternatively CTA_FILTER could have been used for the same > functionality. However it is not yet supported during flush requests and > is only available when using AF_INET or AF_INET6. For the record, this is applied to nf-next.