[ovs-discuss] OVS 2.3.0 issues

[Ben Pfaff]

Pravin, does Linux 3.13 have kernel MPLS support in OVS?

Thanks,

Ben.

On Thu, Sep 18, 2014 at 02:58:33PM -0700, Sangho Shin wrote:
> Hello, Ben,
> 
> We are using pretty much recent kernel version, 3.13.0 released on Sept,
> included in linux 14.04 release.
> 
> Thank you,
> 
> Sangho
> 
> 
> 
> On Mon, Sep 15, 2014 at 8:51 AM, Ben Pfaff <blp at nicira.com> wrote:
> 
> > Thank you for the bug reports!  (In the future I'd suggest one bug
> > report per email because it makes it easier to handle each one.)
> >
> > On Thu, Sep 04, 2014 at 07:05:03PM -0700, Saurav Das wrote:
> > > Possible bug: ovs-ofctl display of actions
> > >
> > > Here is a table-miss-entry which is supposed to match everything. There
> > are
> > > no instructions associated with this entry.
> > >
> > > cookie=0x0, duration=31.700s, table=5, n_packets=7, n_bytes=686,
> > priority=0
> > > actions=drop
> > >
> > > According to the OF1.3 spec, when there are no goto-instructions,
> > pipeline
> > > processing stops, and the action-set should get executed.
> > > We do believe this is what is happening in the switch - however the
> > display
> > > "actions=drop" is misleading, and possibly a holdover from OF1.0
> > behavior,
> > > when no actions meant drop. Perhaps "actions=execute-action-set" may
> > better
> > > reflect OF1.3 behavior when there are no instructions.
> >
> > I can see how that could be misunderstood, but I doubt that we're going
> > to change such a long-standing OVS behavior on that basis.  Certainly
> > not to something as awkward and backward-incompatible as
> > "execute-action-set"!  I think that it's possible to change it to just
> > "actions=" without any actions specified in a backward-compatible
> > manner, and if that's better than I'd consider it.
> >
> > > Possible bug: group stats don't update
> > >
> > > Here is a group definition:
> > >
> > >
> > group_id=536870916,type=indirect,bucket=weight:0,actions=dec_ttl,set_field:00:00:01:01:01:80->eth_src,output:4
> > >
> > > Here are the stats:
> > >
> > >
> > group_id=536870916,duration=202.091s,ref_count=0,packet_count=0,byte_count=0,bucket0:packet_count=0,byte_count=0
> > >
> > > None of the counts go up,  yet I know traffic is being processed by this
> > > group, as there is no other place where I have specified that packets
> > > should go out of port 4.
> >
> > Unfortunately OVS 2.3 does not implement group stats.  They are
> > available on master, though, and will be in OVS 2.4.
> >
> > > Possible bug: group doing MPLS stuff doesn't work
> > >
> > >
> > > Here is the flow that points to the group (as part of the actions written
> > > to an action-set):
> > >
> > > cookie=0x0, duration=31.703s, table=2, n_packets=7, n_bytes=686,
> > > priority=65520,ip,nw_dst=7.7.7.0/24
> > >
> > actions=write_actions(push_mpls:0x8847,set_field:103->mpls_label,group:2684354566),goto_table:5
> > >
> > > In table 5, the packets hit the table-miss-entry, which has no
> > > instructions, so the action-set gets executed.
> > >
> > > Here is the group definition:
> > >
> > >
> > group_id=2684354566,type=indirect,bucket=weight:0,actions=dec_mpls_ttl,set_field:00:00:01:01:01:80->eth_src,set_field:00:00:02:02:02:80->eth_dst,output:6
> > >
> > > Here are the error messages we see in the logs:
> > >
> > >
> > > 2014-08-29T23:58:53.367Z|00001|dpif(handler358)|WARN|system at ovs-system:
> > > failed to put[create] (Invalid argument)
> > >
> > dp_hash(0/0),recirc_id(0),skb_priority(0),in_port(5),skb_mark(0/0),eth(src=00:00:00:00:02:01,dst=00:00:01:01:01:80),eth_type(0x0800),ipv4(src=
> > >
> > 10.0.2.1/255.255.255.255,dst=7.7.7.7/255.255.255.255,proto=1/0xff,tos=0/0xfc,ttl=64/0xff,frag=no/0xff
> > ),icmp(type=8,code=0),
> > >
> > actions:set(eth(src=00:00:01:01:01:80,dst=00:00:02:02:02:80)),push_mpls(label=103,tc=0,ttl=63,bos=1,eth_type=0x8847),7
> > >
> > > 2014-08-29T23:58:53.367Z|00002|dpif(handler358)|WARN|system at ovs-system:
> > > execute
> > >
> > set(eth(src=00:00:01:01:01:80,dst=00:00:02:02:02:80)),push_mpls(label=103,tc=0,ttl=63,bos=1,eth_type=0x8847),7
> > > failed (Invalid argument) on packet
> > >
> > icmp,metadata=0,in_port=0,vlan_tci=0x0000,dl_src=00:00:00:00:02:01,dl_dst=00:00:01:01:01:80,nw_src=10.0.2.1,nw_dst=7.7.7.7,nw_tos=0,nw_ecn=0,nw_ttl=64,icmp_type=8,icmp_code=0
> >
> > Hmm, that's a strange error.  Are you by chance running an older kernel
> > module that doesn't support the MPLS actions?  Userspace should detect
> > that and fall back to implementing MPLS itself, but it's possible that
> > that logic is failing.
> > _______________________________________________
> > discuss mailing list
> > discuss at openvswitch.org
> > http://openvswitch.org/mailman/listinfo/discuss
> >