topic Re: Memory Event Type : Single bit error (SBE) event. in Operating System - HP-UX

Memory Event Type : Single bit error (SBE) event.

Joseph Samuel — Mon, 12 Feb 2007 00:37:04 GMT

HI,The following EMS occurred in syslog of one of the server.pls provide me a solution

Memory Event Type : Single bit error (SBE) event. A correctable single bit error has been detected and logged.

Re: Memory Event Type : Single bit error (SBE) event.

John Payne_2 — Mon, 12 Feb 2007 00:49:41 GMT

A correctable Single Bit memory error in and of itself is not a bad thing, there was a problem that was fixed. It's the double bit errors you want to avoid and worry about.

Do you have Online diagnostics installed? (cstm or xstm) Go into the diagnostics, select your memory, and run info on it. You will get a list of all memory errors. I wouldn't worry about one or two single bit errors, but if you are getting a bunch of them, you may want to have that memory replaced. (If you have a support contract, just open an issue and post the memory log from the diagnostics.)

You don't even have to go into the diagnostics if you don't want to, you can parse it all into the command line and wait for the output:

echo "selclass qualifier memory;info;wait;infolog" |/usr/sbin/cstm

=-+-=-+-=-+-=-+-=-+-=-+-=-+-=-+-=-+-=-+-=-+-=-+-=-+-=-+-=-+-=-+-=-+-=-+-=-+-=

-- Information Tool Log for MEMORY on path 2/5 --

Log creation time: Sun Feb 11 22:47:36 2007

Hardware path: 2/5

Basic Memory Description

Module Type: MEMORY
Total Configured Memory : 32768 MB
Page Size: 4096 Bytes

Memory interleaving is supported on this machine and is ON.

Memory Board Inventory

CAB/CELL: 0/0

DIMM A DIMM B DIMM C DIMM D
Slot Size (MB) Size (MB) Size (MB) Size (MB)
---- --------- --------- --------- ---------
0 1024 1024 1024 1024
1 1024 1024 1024 1024
2 1024 1024 1024 1024
3 1024 1024 1024 1024

Cell Total (MB): 16384
-------------------------------------------------

CAB/CELL: 0/2

DIMM A DIMM B DIMM C DIMM D
Slot Size (MB) Size (MB) Size (MB) Size (MB)
---- --------- --------- --------- ---------
0 1024 1024 1024 1024
1 1024 1024 1024 1024
2 1024 1024 1024 1024
3 1024 1024 1024 1024

Cell Total (MB): 16384
-------------------------------------------------

System Total (MB): 32768

Memory Error Log Summary

Error
CAB/CELL DIMM Error Address Error Type Page Count
------------- ----------------- ---------- --------- -----
0/0 0D 0x000000005f652800 Single-Bit 0x005f652 1

System start: Mon Feb 6 05:23:17 2006.
Last error check: Sun Feb 11 22:45:47 2007.
Logging interval: 3600 seconds.
1 address(es) with errors logged by memory logging daemon.

The Logtool Utility provides full details about the memory error log.

Page Deallocation Table (PDT)

PDT Entries Used: 0
PDT Entries Free: 200
PDT Total Size: 200

This machine of mine had 1 single bit memory error registered on it. I'm ignoring it for now.

Hope it helps
John

Re: Memory Event Type : Single bit error (SBE) event.

Mridul Shrivastava — Mon, 12 Feb 2007 01:01:59 GMT

If you have cstm installed then execute the following command and check both files one by one:
# echo "gop cstmpager cat;scl type mem;info;wait;il"|cstm > /tmp/mem.out
# echo "gop cstmpager cat;ru l\nvd\n"|cstm > /tmp/memvd.out

If there are multiple error on the same page (memory address) then there is nothing to worry about and a reboot will resolve the issue. ( You will have lots of PDT entries free). This is the case because that page is locked by OS hence causing multiple SBEs on the same page so reboot will release the page and no further SBEs on that perticular page.

However If SBEs are caused on multiple pages then that memory module needs replacement ( lots of PDT entries would have been used).

Re: Memory Event Type : Single bit error (SBE) event.

Reshma Malusare — Mon, 12 Feb 2007 01:26:56 GMT

Hi Joseph,
Single bit error is not very serious unless you will get many errors regularly.
The error persist after 1 GB RAM and one memory board replacement.
The bad memory was not pinpointed, and the memory and memory board replacement did not remove it.
NOTE: To troubleshoot single bit errors, always take the memory down to base. Add memory back one set at a time until the
error reappears.
Please refer follwoing link where you will get many such type of similar incidents and their solutions.
http://docs.hp.com/en/diag/ems/memory_ia64.htm?jumpid=reg_R1002_USEN

Check following links:
http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?lang=en&cc=us&objectID=tis11585&jumpid=reg_R1002_USEN#top

Re: Memory Event Type : Single bit error (SBE) event.

Torsten. — Mon, 12 Feb 2007 02:06:40 GMT

Re: Memory Event Type : Single bit error (SBE) event.

Reshma Malusare — Mon, 12 Feb 2007 04:09:37 GMT

Hi,
if your query is solved then please assign points.
Regards
Reshma

Re: Memory Event Type : Single bit error (SBE) event.

Andrew Merritt_2 — Mon, 12 Feb 2007 10:09:53 GMT

Joseph,
I would recommend installing a current version of the OnlineDiags. You have A.45.00, which is the June 2004 release. See http://www.docs.hp.com/en/diag/stm/stm_upd.htm#table

The currently supported versions, A.52.00 and A.53.00, do not report individual SBEs, only repeated ones which would indicate a hardware problem that requires action.

Andrew