Cisco Cisco Content Delivery Engine 250 Guida All'Installazione
1 Background
Current CDE250 systems utilize an Intelligent Platform Management Interface (IPMI)
infrastructure that monitors and manages the health of the system. This is implemented using
embedded IPMI firmware running within the Baseboard Management Controller (BMC) system
chip on the motherboard. The current version of IPMI firmware used on the CDE250 is v1.33.
There are currently three (3) known problems associated with the IPMI / BMC subsystem and
the IPMI FW version 1.33.
1) CPU usage of [kipmi0] process periodically consumes ~ 100% utilization.
This was recently reported in the following SR customer case:
This was recently reported in the following SR customer case:
SR-624629217 - CDRENS05 / 2.6.3b45 / new CDE250-2S6 CPU usage
An IBM linux kernel article described this issue as follows:
“ The increased CPU usage of [kipmi] is normal. The hardw are interface (BMC) is not
interrupt driven, so the driver must poll the device for status and messages. It is this polling
that is show ing up as a busy CPU. The [kipmi] kernel thread has its priority intentionally
low ered so that it does not interfere w ith other processes on the system. Even w hen it is
polling in its tightest loop (usually w hen it thinks the BMC has active events it needs to
handle), it w ill give up the CPU to any process that w ants it.
interrupt driven, so the driver must poll the device for status and messages. It is this polling
that is show ing up as a busy CPU. The [kipmi] kernel thread has its priority intentionally
low ered so that it does not interfere w ith other processes on the system. Even w hen it is
polling in its tightest loop (usually w hen it thinks the BMC has active events it needs to
handle), it w ill give up the CPU to any process that w ants it.
“
Due to a defect in earlier versions of IPMI firmware (including v1.33), this polling
mechanism was inefficient, often times resulting in high CPU usage. The Cisco supplier of
the CDE250 systems has released a new version of IPMI firmware (v2.05), that resolves this
CPU utilization issue. We have validated this new firmware internally at Cisco and
confirmed it acceptably minimizes [kipmi] CPU usage. IPMI v2.05 firmware will be
shipped on all new CDE250 systems out of manufacturing. Please follow the procedure
described in Chapter 2 to upgrade the IPMI firmware to v2.05.
mechanism was inefficient, often times resulting in high CPU usage. The Cisco supplier of
the CDE250 systems has released a new version of IPMI firmware (v2.05), that resolves this
CPU utilization issue. We have validated this new firmware internally at Cisco and
confirmed it acceptably minimizes [kipmi] CPU usage. IPMI v2.05 firmware will be
shipped on all new CDE250 systems out of manufacturing. Please follow the procedure
described in Chapter 2 to upgrade the IPMI firmware to v2.05.
2) IPMI Watchdog error messages in kernel system log.
The following IPMI messages periodically occur in the kernel system log (syslog.txt):
The following IPMI messages periodically occur in the kernel system log (syslog.txt):
%SE-SYS-3-900000: IPMI Watchdog: response: Error ff on cmd 22
%SE-SYSMON-3-445000: Error in sdt read (hang), restart sdt.
The following customer SR cases have been raised against this issue:
SR-623932327 - Failure of the Cisco CDE -250 Box.