On Wed, Nov 6, 2019 at 5:01 PM Yi Yang (杨燚)-云服务集团 <[email protected]> wrote:
> Thanks Darrell, I didn’t receive your second reply, I saw it in > mail.openvswitch.org. > > > > “ > > probably, you should give an example of what you mean by above > > I am not sure you are meaning to say that you want to specify an L4 port in > > your > > snat action rule or not; you will want to use ephemeral ports by not > > specifying a > > specific port in most cases > > “ > > > > For SNAT, we don’t specify port, just use default port range > “1024-65535”), but for internal source IPs, i.e. floating IPs, they are > discrete in most cases because some floating IPs needn’t access Internet, > for public IPs, so are they. For public IPs, maybe they are from different > telecom carriers, we prefer egress traffic can be distributed on several > BGP lines. > > > > table=0,ip,nw_src=172.18.0.67,…,actions=ct(commit,table=0,zone=1,nat(src=220.0.0.3,230.0.0.7,240.0.0.123)) > > > table=0,ip,nw_src=172.18.0.80,…,actions=ct(commit,table=0,zone=1,nat(src=220.0.0.3,230.0.0.7,240.0.0.123)) > > > table=0,ip,nw_src=172.19.0.23,…,actions=ct(commit,table=0,zone=1,nat(src=220.0.0.3,230.0.0.7,240.0.0.123)) > > > > Ideally, we hope, for different traffic types from the same internal IP > (say 172.18.0.67), some can SNAT to 220.0.0.3, some can SNAT to 230.0.0.7, > some can SNAT to > > 240.0.0.123, that way, they can leverage total bandwidth of several BGP > lines. > > > > I know current OVS can’t support the above IP list for snat, but it is > indeed required in reality, I don’t understand why OVS can’t do in this > way, is it linux conntrack limitation or what else reason? I think it is > similar to IP range which can be supported. > Presently, the limitation is both at the Openflow layer and implementation details at datapath The layer above (a controller or even a script) can do the mapping taking into account the desired distribution A controller can/will often do this and similar types of configuration specification. > > > > *发件人:* Darrell Ball [mailto:[email protected]] > *发送时间:* 2019年11月6日 9:38 > *收件人:* Yi Yang (杨燚)-云服务集团 <[email protected]> > *抄送:* [email protected]; [email protected] > *主题:* Re: [ovs-dev] can OVS conntrack support IP list like this: > actions=ct(commit, table=0, zone=1, nat(dst=220.0.0.3, 220.0.0.7, > 220.0.0.123))? > > > > > > > > On Tue, Nov 5, 2019 at 4:32 PM Yi Yang (杨燚)-云服务集团 <[email protected]> > wrote: > > Hi, folks > > > > We need to do SNAT for many internal IPs by just using several public IPs, > we also need to do DNAT by some other public IPs for exposing webservice, > openflow rules look like the below: > > > > table=0,ip,nw_src=172.17.0.0/16, > …,actions=ct(commit,table=0,zone=1,nat(src= > 220.0.0.3,220.0.0.7,220.0.0.123)) > > table=0,ip,nw_src=172.18.0.67,…,actions=ct(commit,table=0,zone=1,nat(src=22 > 0.0.0.3,220.0.0.7,220.0.0.123)) > > > > for snat, you can map some subset of private IPs to a given public IP and > so on > > > > > > table=0,ip,tcp,nw_dst=220.0.0.11,tp_dst=80,…,actions=ct(commit,table=0,zone > =2,nat(dst=172.16.0.100:80)) > > table=0,ip,tcp,nw_dst=220.0.0.11, > tp_dst=443,…,actions=ct(commit,table=0,zone=2,nat(dst=172.16.0.100:443)) > > > > you are mapping 'to' private IPs, so you have control over the range > > > > > > > > > From ct document, it seems it can’t support IP list for nat, anybody knows > how we can handle such cases in some kind feasible way? > > > > In addition, is it ok if multiple openflow rules use the same NAT IP:PORT > combination? I’m not sure if it will result in some conflicts for SNAT, > because all of them need to do dynamic source port mapping, per my test, it > seems this isn’t a problem. > > > > IIUC, as long as tuples are unique, it should be fine > > > > > > > Thank you all in advance and appreciate your help sincerely. > > _______________________________________________ > dev mailing list > [email protected] > https://mail.openvswitch.org/mailman/listinfo/ovs-dev > > _______________________________________________ dev mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-dev
