[c-nsp] SUP720 TFIB scan not completing

[Christian Bering]

Hi all,

Earlier today we started seeing the following messages on a SUP720 in
our network:

Jan 24 22:45:24.014 MET: %TFIB-SP-7-SCANSABORTED: TFIB scan not
completing.  MAC string updated.
-Traceback= 40C32E2C 40C331AC 40C09FE0 40C0A580 40BF06D8 40BF0AF0
40BF0DCC 40BF19C8
Jan 24 22:45:49.522 MET: %TFIB-7-SCANSABORTED: TFIB scan not completing.
MAC string updated.
-Traceback= 41EB455C 41EB48DC 405233CC 405240F0 40699230 406998BC
4069A4E0 4008AB54

CPU utilization was at 100%:

#show proc cpu | ex 0.00
CPU utilization for five seconds: 99%/1%; one minute: 99%; five minutes:
99%
 PID Runtime(ms)   Invoked      uSecs   5Sec   1Min   5Min TTY Process
   5      177464     31490       5635  4.10%  0.94%  1.01%   0 Check
heaps
   8       29148    143305        203  0.07%  0.03%  0.04%   0 ARP Input
  26        7128      5161       1381  0.07%  0.06%  0.07%   0 HC
Counter Timer
 115     2187696    284021       7702 91.24% 88.63% 88.40%   0 CEF
Scanner
 118       40632    431972         94  0.07%  0.06%  0.05%   0 IP Input
 154       48560     24386       1991  0.07%  0.22%  0.17%   0 IP RIB
Update
 167        4596     22184        207  0.07%  0.02%  0.01%   0 CEF
process
 288       19060    563793         33  0.07%  0.07%  0.07%   0 Standby
(HSRP)
 292        6024     58523        102  0.07%  0.05%  0.06%   0 ISIS Adj
 296        4304     47582         90  0.07%  0.06%  0.05%   0 ISIS Upd
 309      403040    173895       2317  1.62%  3.23%  2.99%   0 BGP
Router

Clearing route tables etc. did nothing. I finally rebooted the router
and then it ran fine for about 4 hours. However, right after this router
came back up, a neighbouring router started exhibiting the same
behaviour. The two rouers are connected via both L2 and L3 links and are
now both acting this way. I am puzzled.

Sofware version is. 12.2(18)SXE3

What should I look for?

Thanks,
Christian