Two issues for IxNetwork when set eBGP by Scenario

Ixia updates NexGen framework in IxNetwork, that is great function and help tester simplified workload, but looks like the function couldn’t completely automate,  e.g when you config local address, GW address couldn’t auto-generate, you must manually change that, that should ok, everybody should fix that~ 🙂  But some issue will waste your time to troubleshooting. Summary two issues for the article that will help you fast to fix similar issues.

My IxNetwork version is 7.40.929.28.GA, GA version, wish to fix those issues at MR version 🙂

MALFORM update error on NCS5500

eBGP neighbor and route normal, only have alarm

RP/0/RP0/CPU0:Aug 10 00:05:58.711 UTC: bgp[1060]: %ROUTING-BGP-3-MALFORM_UPDATE : Malformed UPDATE message received from neighbor 3:30:1::2 (VRF: default) - message length 78 bytes, error flags 0x00400000, action taken "DiscardAttr". Error details: "Error 0x00400000, Field "Attr-unexpected", Attribute 5 (Flags 0x40, Length 4), Data [400504]". NLRIs: [IPv6 Unicast] 3000:0:1:1::/64 

Have followed alarms after enable debug

RP/0/RP0/CPU0:Aug 10 00:21:31.405 UTC: bgp[1060]: [default-iord]: Receive message dump for 3:30:1::2:
RP/0/RP0/CPU0:Aug 10 00:21:31.405 UTC: bgp[1060]: [default-iord]: ffff ffff ffff ffff ffff ffff ffff ffff 
RP/0/RP0/CPU0:Aug 10 00:21:31.405 UTC: bgp[1060]: [default-iord]: 0013 04 
RP/0/RP0/CPU0:Aug 10 00:21:31.405 UTC: bgp[1060]: [default-iord]: KEEPALIVE received from 3:30:1::2
RP/0/RP0/CPU0:Aug 10 00:21:31.405 UTC: bgp[1060]: [default-iowt]: bgp write for afi 5 for neighbor 3:30:1::2 (fd 475)
RP/0/RP0/CPU0:Aug 10 00:21:31.405 UTC: bgp[1060]: [default-rtr]: Ignoring local preference attribute (3:30:1::2 is not under common administration)
RP/0/RP0/CPU0:Aug 10 00:21:31.405 UTC: bgp[1060]: [default-rtr]: !!!!!!!!!!!!!:: ERROR_HANDLING<<3:30:1::2>> :: errfl=0x00400000, attrfl=0x40, attrcode=5, attrlen=4:: errhenabled=1, action=5:: MSG=0x7f5f080024c8 (fl=0x00400000, finalaction=5, elemcount=1):: msglindex=0, msgcount=16
RP/0/RP0/CPU0:Aug 10 00:21:31.405 UTC: bgp[1060]: [default-rtr]: UPDATE from 3:30:1::2 contains nh 3:30:1::2/128, gw_afi 5, flags 0x20000, nlri_afi 5
RP/0/RP0/CPU0:Aug 10 00:21:31.405 UTC: bgp[1060]: [default-rtr]: NH-Validate-Create: addr=3:30:1::2/128, len=16, nlriafi=5, nbr=3:30:1::2, gwafi=5, gwlen=32, gwaddrlen=128::: nhout=0x0x7f5f3c9ce7dc, validity=1, attrwdrflags=0x00000000
RP/0/RP0/CPU0:Aug 10 00:21:31.405 UTC: bgp[1060]: [default-rtr]: --bgp4_rcv_attributes--: END: nbr=3:30:1::2:: msg=0x0x7f5f50783a80/78, updlen=59, attrbl=0x0x7f5f50783a97/55, ipv4reachlen=0, msginpath=0x0x7f5f1f7c5928, asloopcheck=1, attrwdrfl=0x00000000:: samecluster=0, local_as_prepended=0, attr_wdr_flags 0x00000000, myascount=0:: rcvdata=0x0x7f5f50783ace/0, errptr=0x0x7f5f50783aad/33
RP/0/RP0/CPU0:Aug 10 00:21:31.405 UTC: bgp[1060]: [default-rtr] (ip6u): Received UPDATE from 3:30:1::2 with attributes: 
RP/0/RP0/CPU0:Aug 10 00:21:31.405 UTC: bgp[1060]: [default-rtr] (ip6u): nexthop 3:30:1::2/128, origin i, path 306 306
RP/0/RP0/CPU0:Aug 10 00:21:31.405 UTC: bgp[1060]: [default-rtr] (ip6u): Received prefix 3000:0:1:1::/64 (path ID: none) from 3:30:1::2
RP/0/RP0/CPU0:Aug 10 00:21:31.405 UTC: bgp[1060]: %ROUTING-BGP-3-MALFORM_UPDATE : Malformed UPDATE message received from neighbor 3:30:1::2 (VRF: default) - message length 78 bytes, error flags 0x00400000, action taken "DiscardAttr". Error details: "Error 0x00400000, Field "Attr-unexpected", Attribute 5 (Flags 0x40, Length 4), Data [400504]". NLRIs: [IPv6 Unicast] 3000:0:1:1::/64 
RP/0/RP0/CPU0:Aug 10 00:21:31.405 UTC: bgp[1060]: [default-rtr]: !!-!-#-!-#-!!:: Received Malformed UPDATE from nbr 3:30:1::2:: msglen=78, errflags=0x00400000, finalaction=DiscardAttr:: elemcount=1, lastelem={"Error 0x00400000, Field "Attr-unexpected", Attribute 5 (Flags 0x40, Length 4), Data [400504]"}:: ERRCTX={{msglindex=0, malformcount=16, memfailcount=0}}

Resolved

This is expected behavior for Ixia, which is ebgp peer, sending local pref. According to present logic, local pref attr from ebgp peer will be rejected. Ixia should disable the flag when change Type to “External” from “Internal” (iBGP -> eBGP) in future.

Couldn’t learn any eBGP route on NCS5500

Have followed alarms after enable debug

RP/0/RP0/CPU0:Aug 10 00:36:58.351 UTC: bgp[1060]: [default-iord]: Received message from 3:30:1::2 with type 4, length (incl. header) 19
RP/0/RP0/CPU0:Aug 10 00:36:58.351 UTC: bgp[1060]: [default-iord]: Receive message dump for 3:30:1::2:
RP/0/RP0/CPU0:Aug 10 00:36:58.351 UTC: bgp[1060]: [default-iord]: ffff ffff ffff ffff ffff ffff ffff ffff 
RP/0/RP0/CPU0:Aug 10 00:36:58.351 UTC: bgp[1060]: [default-iord]: 0013 04 
RP/0/RP0/CPU0:Aug 10 00:36:58.351 UTC: bgp[1060]: [default-iord]: KEEPALIVE received from 3:30:1::2
RP/0/RP0/CPU0:Aug 10 00:36:58.351 UTC: bgp[1060]: [default-iowt]: bgp write for afi 5 for neighbor 3:30:1::2 (fd 457)
RP/0/RP0/CPU0:Aug 10 00:36:58.351 UTC: bgp[1060]: [default-rtr]: UPDATE from 3:30:1::2 contains nh 3:30:1::2/128, gw_afi 5, flags 0x20000, nlri_afi 5
RP/0/RP0/CPU0:Aug 10 00:36:58.351 UTC: bgp[1060]: [default-rtr]: NH-Validate-Create: addr=3:30:1::2/128, len=16, nlriafi=5, nbr=3:30:1::2, gwafi=5, gwlen=32, gwaddrlen=128::: nhout=0x0x7f5f3c9ce7dc, validity=1, attrwdrflags=0x00000000
RP/0/RP0/CPU0:Aug 10 00:36:58.351 UTC: bgp[1060]: [default-rtr]: aspath loop detect failed due to finding our own AS 1
RP/0/RP0/CPU0:Aug 10 00:36:58.351 UTC: bgp[1060]: [default-rtr]: --bgp4_rcv_attributes--: END: nbr=3:30:1::2:: msg=0x0x7f5f50783a80/71, updlen=52, attrbl=0x0x7f5f50783a97/48, ipv4reachlen=0, msginpath=0x0x7f5f1f7c5928, asloopcheck=1, attrwdrfl=0x00000800:: samecluster=0, local_as_prepended=0, attr_wdr_flags 0x00000800, myascount=0:: rcvdata=0x0x7f5f50783ac7/0, errptr=0x0x7f5f50783aa6/33
RP/0/RP0/CPU0:Aug 10 00:36:58.351 UTC: bgp[1060]: [default-rtr] (ip6u): Received unreachables from 3:30:1::2: attrcode=14, attrwdrflags=0x00000800
RP/0/RP0/CPU0:Aug 10 00:36:58.351 UTC: bgp[1060]: [default-rtr] (ip6u): UPDATE from 3:30:1::2 with attributes:
RP/0/RP0/CPU0:Aug 10 00:36:58.351 UTC: bgp[1060]: [default-rtr] (ip6u): nexthop 3:30:1::2/128, origin i, path 306 1
RP/0/RP0/CPU0:Aug 10 00:36:58.351 UTC: bgp[1060]: [default-rtr] (ip6u): UPDATE from 3:30:1::2, prefix 3000:0:1:1::/64 (path ID: none) DENIED due to: 
RP/0/RP0/CPU0:Aug 10 00:36:58.351 UTC: bgp[1060]: [default-rtr] (ip6u):  as-path contains our own AS, or 0;

Resolved

Easy found reason from debug, that due to NCS5500 “aspath loop detect failed due to finding our own AS 1”, so discard the update. That is normal behavior for ixia(default AS-Path is 1), ixia couldn’t auto change as path of prefix pool if you change local AS to non-default, will match the issue if your DUT use BGP 1.

Suggestion

When you set up eBGP + Prefix Pool by IXIA Scenario, suggest change follow procedure:

  1. adjust device group multiplier, default is 10, I usually set 1
  2. adjust vlan if have in Ethernet level
  3. adjust address and gateway in IPv4 level
  4. adjust “DUT IP”, “Local AS” and “Type” in BGP Peer level
  5. add Prefix Pool, default 1 prefix, if need increase prefix, suggest direct adjust by “network Group Multiplier”, but not adjust “Count of network address”
  6. adjust “override peer as” and “do not include local as” in “AS Path”/ “BGP IP Route Range” / Prefix Pool
  7. adjust default AS number in “ASPathSegments”, default is 1, if your BGP AS is 1, that will report alarm and ignore the update
  8. adjust “Local Preference” to disable in “Advanced” / “BGP IP Route Range” / “Prefix Pool”.
本文出自 Frank's Blog

版权声明:


本文链接:Two issues for IxNetwork when set eBGP by Scenario
版权声明:本文为原创文章,仅代表个人观点,版权归 Frank Zhao 所有,转载时请注明本文出处及文章链接
你可以留言,或者trackback 从你的网站

留言哦

blonde teen swallows load.xxx videos