topic Re: Match problem in Flow MOD (COMPLEMENT) in Software Defined Networking

Match problem in Flow MOD

sbotkine — Fri, 21 Mar 2014 10:26:50 GMT

Hello,

I have 4 HP switch with the same configuration.

Here is the match field I've just created:

MutableMatch match = MatchFactory.createMatch(PV);
match = MatchFactory.createMatch(version);
match.addField(FieldFactory.createBasicField(PV, OxmBasicFieldType.ETH_TYPE, EthernetType.ARP));

When I execute my bundle, only 2 from my 4 switch received the flow mod.

Here is the trace I can see on the "OpenFlow trace":

11:05:08.282MESSAGE_TX00:14:f0:92:1c:21:fa:c0{ofm:[V_1_3,FLOW_MOD,88,2027],cmd=ADD,match={Match(V_1_3):[type=OXM,len=10],fields=ETH_TYPE},...}
11:05:08.282MESSAGE_TX00:14:f0:92:1c:21:fa:c0{ofm:[V_1_3,BARRIER_REQUEST,8,2027]}

11:05:08.210MESSAGE_TX00:14:c0:91:34:e7:b5:c0{ofm:[V_1_3,FLOW_MOD,88,2025],cmd=ADD,match={Match(V_1_3):[type=OXM,len=10],fields=ETH_TYPE},...}
11:05:08.210MESSAGE_TX00:14:c0:91:34:e7:b5:c0{ofm:[V_1_3,BARRIER_REQUEST,8,2025]}
11:05:08.212MESSAGE_RX00:14:c0:91:34:e7:b5:c0{ofm:[V_1_3,ERROR,76,2025],BAD_MATCH/BAD_FIELD,#dataBytes=64,OFM-cause:[V_1_3,FLOW_MOD,88,2025]}
11:05:08.212MESSAGE_RX00:14:c0:91:34:e7:b5:c0{ofm:[V_1_3,BARRIER_REPLY,8,2025]}

11:05:08.246MESSAGE_TX00:14:f0:92:1c:21:a8:40{ofm:[V_1_3,FLOW_MOD,88,2026],cmd=ADD,match={Match(V_1_3):[type=OXM,len=10],fields=ETH_TYPE},...}
11:05:08.246MESSAGE_TX00:14:f0:92:1c:21:a8:40{ofm:[V_1_3,BARRIER_REQUEST,8,2026]}

11:05:08.167MESSAGE_TX00:14:3c:4a:92:fa:cd:80{ofm:[V_1_3,FLOW_MOD,88,2024],cmd=ADD,match={Match(V_1_3):[type=OXM,len=10],fields=ETH_TYPE},...}
11:05:08.168MESSAGE_TX00:14:3c:4a:92:fa:cd:80{ofm:[V_1_3,BARRIER_REQUEST,8,2024]}
11:05:08.169MESSAGE_RX00:14:3c:4a:92:fa:cd:80{ofm:[V_1_3,ERROR,76,2024],BAD_MATCH/BAD_FIELD,#dataBytes=64,OFM-cause:[V_1_3,FLOW_MOD,88,2024]}

The flow mod worked for switch 14:f0:92:1c:21:fa:c0 and switch 14:f0:92:1c:21:a8:40 and failed for 14:c0:91:34:e7:b5:c0 and 14:3c:4a:92:fa:cd:80.

The Error returned by the switches is: BAD_MATCH/BAD_FIELD.

If my match is wrong, why does it work for two switches and failes for the rest ?

Re: Match problem in Flow MOD (COMPLEMENT)

sbotkine — Sat, 22 Mar 2014 09:51:50 GMT

If I replace

match.addField(FieldFactory.createBasicField(PV, OxmBasicFieldType.ETH_TYPE, EthernetType.ARP));

with

match.addField(FieldFactory.createBasicField(PV, OxmBasicFieldType.ETH_TYPE, EthernetType.IPv4));

the flow mod works in all my switchs.

With the ARP entry, It work only on two switch, that is very curious ?

Re: Match problem in Flow MOD (COMPLEMENT)

sbotkine — Sat, 22 Mar 2014 10:14:13 GMT

I found a solution. I've put:

match.addField(FieldFactory.createBasicField(PV, OxmBasicFieldType.ETH_TYPE, EthernetType.ARP));

match.addField(FieldFactory.createBasicField(PV, OxmBasicFieldType.ARP_OP, Arp.OpCode.REQ.code()));

But I don't know why ? If you can explain, I will be happy...

Re: Match problem in Flow MOD (COMPLEMENT)

ShaunWackerly — Tue, 25 Mar 2014 00:07:11 GMT

Hi sbotkine,

This all depends on which HP switches you're sending the flow-mod to and how they're configured. Any switches which have v2 modules only ("no allow-v1-modules") such as the 5400 or 8200, or switches which exclusively have v2 modules such as the 3800 (or slight variant 2920) will support matching ARP packets in table 100 (OpenFlow 1.3). If you are using a 5400, 8200 (with v1 modules allowed) or a 3500 (exclusively v1 modules) then matching against ARP packets in table 100 will be rejected by the switch.

Could you post the model of switch(es) that work and switch(es) that don't with the code you posted above? I don't see why adding the ARP_OP line would cause it to work on v1 modules.

Re: Match problem in Flow MOD (COMPLEMENT)

sbotkine — Tue, 25 Mar 2014 09:25:12 GMT

I have:

2 x HP 3800-24G-2SFP (J9575A)

2x HP 3500-24G (J8692A)

But the flow mod installed correctly on one HP3800 and one HP3500, and didn't installed on the other HP3800 and the other HP 3500. That's strange.

Re: Match problem in Flow MOD (COMPLEMENT)

sdnindia — Sat, 12 Apr 2014 17:49:31 GMT

Hello sbotkine,

In table 100 match on ARP packets (on V2 blades) is supported. But match on ARP opcode is not allowed (supported in SW tables only). So it looks like when you add ARP opcode as match field, flows are installed in SW tables. When we say flows will get installed in SW tables, it may be because HP’s controller is already aware of the fact that such flows cannot go into Table 100 and therefore it may push the same flow into Table 200 which would be a software table. A dump of flows installed in the switch will help clarify in which tables the flows sit inside the switch.

Not convinced about the first attempt 3800 failure. Can you provide the following ?

1) Switch image version.

2) Running config.

3) Wireshark capture of the flow mod and error response.

Thanks,

HP SDN Team