NXOS 9.3(5) - C9332C "show spanning-tree detail" parser error

Hi,

Getting this error:

Missing keys: [['rapid_pvst', 'vlans', 1, 'interfaces', 'Port-channel1', 'timers'], ['rapid_pvst', 'vlans', 50, 'interfaces', 'Port-channel1', 'timers'], ['rapid_pvst', 'vlans', 51, 'interfaces', 'Port-channel1', 'timers'], << Ommited a ton of similar output >> ]]
  File "/opt/genie/poc/basic.py", line 88, in learn_stp
    abc = dev.parse('show spanning-tree detail')
  File "/opt/genie/poc/basic.py", line 354, in <module>
    aetest.main()

here’s a sample of “show spanning-tree detail” on that host:

VLAN0001 is executing the rstp compatible Spanning Tree protocol
  Bridge Identifier has priority 0, sysid 1, address aaaa.bbbb.cccc
  Configured hello time 2, max age 20, forward delay 15
  We are the root of the spanning tree
  Topology change flag not set, detected flag not set
  Number of topology changes 0 last change occurred 162:37:09 ago
  Times:  hold 1, topology change 35, notification 2
          hello 2, max age 20, forward delay 15 
  Timers: hello 0, topology change 0, notification 0

 Port 4096 (port-channel1, vPC Peer-link) of VLAN0001 is root forwarding 
   Port path cost 100, Port priority 128, Port Identifier 128.4096
   Designated root has priority 1, address aaaa.bbbb.cccc
   Designated bridge has priority 0, address aaaa.bbbb.cccc
   Designated port id is 128.4096, designated path cost 0
   Timers: message age -38, forward delay 0, hold 0
   Number of transitions to forwarding state: 1
   The port type is network
   Link type is point-to-point by default
   BPDU: sent 292401, received 292410

This host is a Secondary host in a VPC. Perhaps negative timer values are to blame?

It’s still occurring after i ran a “pyats version update”.

[root@localhost poc]# pyats version check
You are currently running pyATS version: 20.8
Python: 3.6.8 [64bit]

  Package                      Version
  ---------------------------- -------
  genie                        20.8
  genie.libs.clean             20.8.1
  genie.libs.conf              20.8
  genie.libs.filetransferutils 20.8
  genie.libs.health            20.8
  genie.libs.ops               20.8
  genie.libs.parser            20.8
  genie.libs.robot             20.8
  genie.libs.sdk               20.8.2
  genie.telemetry              20.8
  genie.trafficgen             20.8
  pyats                        20.8
  pyats.aereport               20.8
  pyats.aetest                 20.8
  pyats.async                  20.8
  pyats.connections            20.8
  pyats.contrib                20.8
  pyats.datastructures         20.8
  pyats.easypy                 20.8
  pyats.kleenex                20.8.1
  pyats.log                    20.8
  pyats.reporter               20.8
  pyats.results                20.8
  pyats.robot                  20.8
  pyats.tcl                    20.8
  pyats.topology               20.8
  pyats.utils                  20.8
  unicon                       20.8.1
  unicon.plugins               20.8.1

[ahersi2-cisco]

Hi Lukeod,

Thanks for the PR, I also submitted the fix on my end, I will update you as soon as the changes are released.

Thank you, Abdurahman

[ahersi2-cisco]

Hi lukeod,

The issue is actually related to the negative timers, good catch. The regex patterns weren’t considering them so only a small fix is needed. The regex saved as p14 on line 632 in the file nxos/show_spanning_tree.py can be updated for the message_age captured group. Simply adding a \-? before \d+ will consider the scenario where the timer is negative. I made the fix on my end and the code will be under review shortly, then I will be able to merge. I can also release a beta for your since our next update will be released in a couple of weeks. We also encourage pull requests which can get merged right away if approved. Let me know if you will make the changes and someone can review the PR right away. Thanks!

Abdurahman