Description

Switch is claiming itself as the root bridge and reporting frequent topology changes, additionally downstream devices are reporting incorrect root bridge when are connected to a QFX5K.

Symptoms

The following logs are also observed.

 

l2cpd[12969]: L2CPD_STP_INDEX_ALLOC_FAILED: Failed to create stp index [ifname ae97 inst 326]":

 

In addition to the above issue, the switch was not programming STP interface in some random ports.

 

-show spanning-tree kernel table only shows 1 kernel index for AE29 , while others show a lot of kernel indexes (see below for more examples)

{master:0}

root@SW> show spanning-tree kernel-table | match ae29

     30 ae29       65535 Forwarding None   26 Enabled    0          0.0.0.0

root@SW>

 

 

root@SW> show spanning-tree kernel-table

STP kernel table

               

STP index Interface Instance State Action Epoch H/W learning Vpls-seq Peer-Ip

     0 GLOBAL     65535 Forwarding None    0 Enabled    0          0.0.0.0

  3766 ae0            1 Forwarding None    1 Enabled    0          0.0.0.0

  1576 ae0            9 Forwarding None    5 Enabled    0          0.0.0.0

   436 ae0           10 Forwarding None    3 Enabled    0          0.0.0.0

  2506 ae0           17 Forwarding None    7 Enabled    0          0.0.0.0

   976 ae0           23 Forwarding None    2 Enabled    0          0.0.0.0

   946 ae0           24 Forwarding None    2 Enabled    0          0.0.0.0

  1216 ae0           25 Forwarding None    1 Enabled    0          0.0.0.0

  1246 ae0           26 Forwarding None    1 Enabled    0          0.0.0.0

   226 ae0           27 Forwarding None    1 Enabled    0          0.0.0.0

   616 ae0           28 Forwarding None   15 Enabled    0          0.0.0.0

 

 

root@SW:RE:0% cprod - A fpc0 -c "show halp-pkt pkt-stats"

rx_pkt_vstp                   : 662509055

rx_pkt_vstp_xlat_miss         : 4257

rx_pkt_vstp_drop              : 661775741

root@SW:RE:0% cprod -A fpc0 -c "show halp-pkt pkt-stats" | grep vstp

rx_pkt_vstp                   : 662509091

rx_pkt_vstp_xlat_miss         : 4257

rx_pkt_vstp_drop              : 661775777

root@SW:RE:0% cprod -A fpc0 -c "show halp-pkt pkt-stats" | grep vstp

rx_pkt_vstp                   : 662509131

rx_pkt_vstp_xlat_miss         : 4257

rx_pkt_vstp_drop              : 661775817

 

Also Queue 43 (STP queue) , the numbers are off , values from rxq_req needs to be same as rxq_success

 

root@SW:RE:0% cprod -A fpc0 -c "show halp-pkt pkt-stats" | grep vstp

rx queue 8 : rxq_req 1624043 rxq_success 1624043

rx queue 14 : rxq_req 6401467 rxq_success 6401434

rx queue 43 : rxq_req 895293389 rxq_success 212602684

 

root@SW:RE:0% cprod -A fpc0 -c "show halp-pkt pkt-stats" | grep 43

rx queue 8 : rxq_req 1624043 rxq_success 1624043

rx queue 14 : rxq_req 6401467 rxq_success 6401434

rx queue 43 : rxq_req 895293556 rxq_success 212602803

 

root@SW:RE:0% cprod -A fpc0 -c "show halp-pkt pkt-stats" | grep 43

rx queue 8 : rxq_req 1624043 rxq_success 1624043

rx queue 14 : rxq_req 6401467 rxq_success 6401434

rx queue 43 : rxq_req 895293587 rxq_success 212602805

 

Solution

To Resolve this error message : l2cpd[12969]: L2CPD_STP_INDEX_ALLOC_FAILED: Failed to create stp index [ifname ae97 inst 326]":

 

Under VSTP stanza, it was configured with interface all and vlan all,  adding individual vlans and interfaces under vstp protocols on the QFX side, will help to clear the error message.

 

The issue is related xSTP not programming the interfaces in STP its fixed in latest Junos code.

 

evo:23.2R2-EVO evo:23.4R1-S1-EVO evo:23.4R2-EVO evo:24.2R1-EVO junos:21.4R3-S5-J19 junos:21.4R3-S7 junos:22.4R3-S2 junos:23.2R2 junos:23.2R2-J14 junos:23.4R1-S1 junos:23.4R2 junos:24.2R1

Modification History

2024-09-26 : Article Created

2024-12-06 : Made Public