[ovs-dev] [PATCH ovn] expr: Combine multiple ipv4 with wildcard mask.(Internet mail)

[gmingchen(陈供明)]

On 2021/4/12, 4:48 PM, "Dumitru Ceara" <dceara at redhat.com> wrote:

    On 4/8/21 1:24 PM, gmingchen(陈供明) wrote:
    > 
    > 
    > On 2021/4/7, 12:01 AM, "Dumitru Ceara" <dceara at redhat.com> wrote:
    > 
    >     On 4/6/21 12:11 PM, Mark Gray wrote:
    >     > I had a conversation with Dumitru and this patch came up in the
    >     > conversation. He made an interesting suggestion (Dumitru, please correct
    >     > me if I get this wrong) that this could be refactored as an external
    >     > tool. This cmdline tool could, for example, take a set of IP addresses
    >     > and return the wildcard representation. For example,
    >     > 
    >     > # ./ovs-new-tool <set of addresses>
    >     > <ip address/prefix> ... <ip address/prefix>
    >     > 
    >     > Then this tool could optionally be used by a CMS. The other advantage of
    >     > this is that it could also be used in other places.
    > 
    >     Given that OVN is essentially a stack of compilers (NB -> SB ->
    >     openflow) I was wondering if it would be reasonable and worth it to go a
    >     step forward and implement this feature to "combine IP addresses with
    >     wildcard" as a library.  This would allow using it at different levels
    >     in the stack, e.g.:
    >     - at CMS level/as a standalone cmdline tool.
    > 
    > My concern is whether the process after cms can correctly handle this
    > non-standard cidr format (1.1.1.0/255.255.255.253).

    I would expect this to not be a problem but it depends on CMS indeed.

Yes.

    > 
    >     - in ovn-northd (for example when generating SB address sets from NB
    >     address sets)
    > 
    > If the non-standard cidr format ip address can be handled reasonably
    > here, I think this is a good idea.

    These are OVN internals so the approach you were proposing in
    ovn-controller could be implemented at this level too.

It is indeed the case.

I wonder if the scale of the IP address is not so important, so that fewer
people respond now. So, I wonder if the patch can be put here first, if
this problem is more common, then further targeted discussion.

    > 
    >     - in ovn-controller (as the current patch is doing).
    > 
    > Thanks,
    > Gongming
    > 

    Thanks,
    Dumitru