Loading...
Loading...
A Cisco Cat3k platform running an IOS-XE release prior to 16.10.1 may experience a crash due to the "PuntInject Keepalive" process. Leading up to this, messages will indicate that "keepalive" packets have not been received for an increasingly long period of time. At 300 seconds, the switch is forced to reload. Eg: %IOSXE_INFRA-4-NO_PUNT_KEEPALIVE: Keepalive not received for 300 seconds %IOSXE_INFRA-2-FATAL_NO_PUNT_KEEPALIVE: Keepalive not received for 300 seconds resetting %Software-forced reload Exception to IOS Thread: Frame pointer 0xFFA06CB6E0, PC = 0xFFEBBEB4C4 UNIX-EXT-SIGNAL: Aborted(6), Process = PuntInject Keepalive Process
This DDTS is specific for Cat3k Platform running IOS-XE release earlier than 16.10.1, including all builds of 16.9.x code and earlier. The issue is not seen in 16.10.1 and later releases due to presence of a newer kernel (MIPS kernel version 4.9) introduced in that IOS version, which has many low-level enhancements to avoid this issue. Contact TAC if you have doubts about this bug. Please note that not all "keepalive" timeouts will be due to this defect. A keepalive is a general term for a diagnostic packet that validates the forwarding path is working, and there are many reasons why keepalives could be dropped.
None. *** Bug will be fixed in 16.12.1 for CAT3K model switches, due to the fact that 16.10.x and 16.11.x code is not available for this platform. ****
On impacted IOS versions, due to a kernel-level issue, there is a lockup occurring within IOS daemon's "fast path" thread, which is used to service packets punted to the control plane. This will cause all packets, including keepalive packets, to fail to be serviced correctly. A potential sign that the "fast path" has stopped servicing packets is if the LSMPI (Linux Shared Memory Punt Interface) as very little or no RX buffers available, suggesting something is causing congestion on the forwarding path to the control plane. For example, something similar to the below could be seen in the crashinfo logs from the event: ========= show platform software infra lsmpi driver ========= LSMPI Driver stat ver: 3 Rings: RX: 4 free 4091 in-use 4096 total <=====
Cisco Integration
Learn more about where this data comes from
Bug Scrub Advisor
Streamline upgrades with automated vendor bug scrubs
BugZero Enterprise
Wish you caught this bug sooner? Get proactive today.