Hi,
The patch makes it work perfectly. Now the Second tag (SPtag) is removed.
But I think there is another bug here.
*First scenario:*
PE1 : set interface l2 tag-rewrite GigabitEthernet5/0/0 push dot1ad
200
PE2 : set interface l2 tag-rewrite GigabitEthernet4/0/1 push dot1ad*
200*
Everything works perfect. the first PE adds the 802.1ad tag of 200 and the
second PE removes it.
*Second scenario:*
PE1 : set interface l2 tag-rewrite GigabitEthernet5/0/0 push dot1ad
200
PE2 : set interface l2 tag-rewrite GigabitEthernet4/0/1 push dot1ad*
120*
I expect the second PE does not pass the packet, since its tag(120) is
different from the received tag(200), (Or in other words they are in
different service provider's vlan. Am I right?)
But unfortunately, the second PE passes it.
I think that the source code is just considering the number of tags, not
the number of tags and their value. I think this is the bug. Am I right??
On Sun, May 27, 2018 at 5:18 PM, Mehran Memarnejad <memarnejad...@gmail.com>
wrote:
> Hi,
> The patch makes it work perfectly. Now the Second tag (SPtag) is removed.
> But I think there is another bug here.
>
> First scenario:
> PE1 : set interface l2 tag-rewrite GigabitEthernet5/0/0 push dot1ad 200
> PE2 : set interface l2 tag-rewrite GigabitEthernet4/0/1 push dot1ad 200
>
> On Sat, May 26, 2018 at 5:51 AM, John Lo (loj) <l...@cisco.com> wrote:
>
>> I just submitted a patch. Can you give it a try if this resolve the
>> problem? -John
>>
>> https://gerrit.fd.io/r/#/c/12750/
>>
>>
>>
>> *From:* Mehran Memarnejad <memarnejad...@gmail.com>
>> *Sent:* Friday, May 25, 2018 1:24 PM
>>
>> *To:* John Lo (loj) <l...@cisco.com>; vpp-dev@lists.fd.io
>> *Subject:* Re: dot1ad tag
>>
>>
>>
>> Without tag-rewrite configuration, everything works well. But I want to
>> activate QinQ feature, so I need to add service provider tag (sp-tag) by
>> using dot1ad tag.
>>
>>
>>
>> Any more idea to solve the problem??
>>
>> On Friday, May 25, 2018, John Lo (loj) <l...@cisco.com> wrote:
>>
>> The tag-rewrite (VTR) configuration looks right. I looked at the
>> l2_vtr_process() function in l2_vtr.h to check how it checks for errors.
>> This is the error drop path:
>>
>>
>>
>> /* if not enough tags to pop then drop packet */
>>
>> if (PREDICT_FALSE ((vnet_buffer (b0)->l2.l2_len - 12) <
>> config->pop_bytes))
>>
>> {
>>
>> return 1;
>>
>> }
>>
>>
>>
>> My guess is that interface-rx-dpo-l2 node did not setup l2_len field in
>> the vnet buffer properly before passing the packet to l2-input node. That’s
>> why tag-rewrite operation on l2-output node does not function properly.
>> If you remove the tag rewrite config from these GigabitEthernet5/0/0
>> customer ports on both PEs, I suppose it should start to work. Any reason
>> you want to have the additional dot1ad tag on the packets for forwarding in
>> the BD and MPLS tunnel?
>>
>>
>>
>> Regards,
>>
>> John
>>
>>
>>
>> *From:* Mehran Memarnejad <memarnejad...@gmail.com>
>> *Sent:* Friday, May 25, 2018 4:40 AM
>> *To:* John Lo (loj) <l...@cisco.com>; vpp-dev@lists.fd.io
>> *Subject:* Re: dot1ad tag
>>
>>
>>
>> Sw_if_index 6 is the mpls tunnel0 and sw_if_index 3 is the
>> GigabitEthernet5/0/0 on which I have set interface tag-rewrite push dot1ad
>> 12 .... (both of them are attached to bridge1)
>>
>>
>>
>> Gigabitethernet5/0/0 is the PE's interface toward customer, meaning that
>> I guess if it does not drop the packet, VPLS will work.
>>
>>
>>
>> The packet is sent to the interface attached to bridge
>> (gigabitethernet5/0/0) by mupls tunnel0.
>>
>> But then the packet drops.
>>
>>
>>
>> On Friday, May 25, 2018, John Lo (loj) <l...@cisco.com> wrote:
>>
>> Hi Mehran,
>>
>>
>>
>> The packet trace shows drop is cause by l2-output node when the packet is
>> sent on the interface with sw_if_index 3 where the output tag-rewrite
>> operation is not expecting packet with a dot1ad tag of 12. What is the
>> interface with sw_if_index of 3 on that PE? Is this the same interface
>> where you have tag-rewrite of “push dot1ad 12” applied?
>>
>>
>>
>> Can you provide the output of “show bridge 1 detail” (assuming bridge
>> domain ID of 1 is used for bd_index 1, otherwise, substitute with the ID
>> used) on that PE, please? The output will show all interfaces in the
>> bridge domain with sw_if_index and tag-rewrite operation configured on each
>> interface.
>>
>>
>>
>> Regards,
>>
>> John
>>
>>
>>
>> *From:* vpp-dev@lists.fd.io <vpp-dev@lists.fd.io> *On Behalf Of *Mehran
>> Memarnejad
>> *Sent:* Thursday, May 24, 2018 8:12 AM
>> *To:* vpp-dev@lists.fd.io
>> *Subject:* [vpp-dev] dot1ad tag
>>
>>
>>
>> Hi,
>>
>> I have configured VPLS in VPP somehow like this link
>> <https://lists.fd.io/g/vpp-dev/message/9112?p=,,,20,0,0,0::Created,,vpls,20,2,0,18122864>
>> .
>>
>>
>>
>> In addition to the above configurations, I want to add a second vlan tag
>> i.e. 802.1ad (QinQ).
>>
>> To achieve this, I entered following command in both PEs:
>>
>> *"Set interface l2 tag-rewrite GigabitEthernet5/0/0 push
>> dot1ad 12"*
>>
>>
>>
>> Tracking what's going on, I found that the first PE adds the QinQ tag
>> (12), but the second PE will not remove this tag and afterward it goes to
>> error node with this message:
>>
>> *"l2-output: L2 output tag rewrite drops"*
>>
>>
>>
>> Here is what *show trace *shows in the second PE:
>>
>>
>>
>> Packet 1
>>
>> 00:31:10:348251: dpdk-input
>> TenGigabitEthernet4/0/0 rx queue 0
>> buffer 0x21b6f: current data 14, length 114, free-list 0, clone-count
>> 0, totlen-nifb 0, trace 0x0
>> ext-hdr-valid
>> l4-cksum-computed l4-cksum-correct l2-hdr-offset 0
>> l3-hdr-offset 14
>> PKT MBUF: port 1, nb_segs 1, pkt_len 128
>> buf_len 2176, data_len 128, ol_flags 0x180, data_off 128, phys_addr
>> 0x4ce6dc40
>> packet_type 0x1 l2_len 0 l3_len 0 outer_l2_len 0 outer_l3_len 0
>> rss 0x0 fdir.hi 0x0 fdir.lo 0x0
>> Packet Offload Flags
>> PKT_RX_IP_CKSUM_GOOD (0x0080) IP cksum of RX pkt. is valid
>> PKT_RX_L4_CKSUM_GOOD (0x0100) L4 cksum of RX pkt. is valid
>> Packet Types
>> RTE_PTYPE_L2_ETHER (0x0001) Ethernet packet
>>
>>
>>
>> MPLS: 00:25:90:97:fa:10 -> a0:36:9f:23:aa:78
>> label 60 exp 0, s 0, ttl 63
>> 00:31:10:348260: mpls-input
>> MPLS: next mpls-lookup[1] label 60 ttl 63 exp 0
>> 00:31:10:348265: mpls-lookup
>> MPLS: next [7], lookup fib index 0, LB index 23 hash 0 label 60 eos 0
>> 00:31:10:348268: lookup-mpls-dst
>> fib-index:0 hdr:[33:64:0:eos] load-balance:21
>> 00:31:10:348270: interface-rx-dpo-l2
>> sw_if_index:6
>>
>>
>>
>>
>>
>>
>>
>>
>> *00:31:10:348272: l2-input l2-input: sw_if_index 6 dst
>> 30:85:a9:f2:23:12 src 3c:07:71:5f:2d:f5 00:31:10:348275: l2-learn
>> l2-learn: sw_if_index 6 dst 30:85:a9:f2:23:12 src 3c:07:71:5f:2d:f5
>> bd_index 1 00:31:10:348277: l2-fwd l2-fwd: sw_if_index 6 dst
>> 30:85:a9:f2:23:12 src 3c:07:71:5f:2d:f5 bd_index 1*
>>
>>
>>
>>
>> *00:31:10:348280: l2-output l2-output: sw_if_index 3 dst
>> 30:85:a9:f2:23:12 src 3c:07:71:5f:2d:f5 data 88 a8 00 0c 81 00 00 06 08 00
>> 45 00*
>>
>>
>>
>>
>> *00:31:10:348282: error-drop l2-output: L2 output tag rewrite drops*
>>
>>
>>
>> Colors: Packet reception , MPLS tag handling, L2 handling, Error
>>
>>
>>
>>
>>
>> If you notice red underlined trace, 802.1ad tag 12 (in hex 0C) and 802.1q
>> tag 6 (in hex 06) has been added to packet.
>>
>>
>>
>>
>>
>> I inspected the code in /src/vnet/l2/l2_vtr.h * l2_vtr_process()*
>> function and /src/vnet/l2/l2_input.h *vnet_update_l2_len()*
>> function, but I couldn't find any problem.
>>
>>
>>
>>
>>
>> MY QUESTION: Is it a bug in code that the 802.1ad tag is not removed?? Or
>> should I have entered more commands?
>>
>>
>>
>> Thanks in advance
>>
>>
>>
>>
>
