topic Re: scsi debugging in Operating System - HP-UX

scsi debugging

R.K. # — Thu, 13 Aug 2009 04:37:55 GMT

Hello All,

I want to enable scsi debugging for 11.31.

Can it be done globally or for a subsystem or only specific to a device?

I tried this for a disk:
-----------------------------------------------
# scsimgr set_attr -a escsi_log_dev=0xbc04b300
Value of attribute escsi_log_dev set successfully
-----------------------------------------------

But cannot find any messages in syslog.log.
Is this the correct way?

And what are the "escsi_dbg_lvl" levels?

Thanks in Advance..

Re: scsi debugging

R.K. # — Thu, 13 Aug 2009 17:54:44 GMT

Any suggestions or advice?

Thanks in advance..

Re: scsi debugging

Steven E. Protter — Thu, 13 Aug 2009 18:07:32 GMT

Shalom,

Try restarting syslog.

/sbin/init.d/syslogd stop
/sbin/init.d/syslogd start

Also why do you expect the logging to be in syslog.log? Is it perhaps in its own file?

lvl stands for level in escsi_log_lvl. Higher levels generally dictate more detail.

Careful this can get verbose.

Why do you need this data? Do you suspect a scsi problem? Inquring minds want to know.

Can it be done globally or for a subsystem or only specific to a device?

Note the dev statement.

I tried this for a disk:
-----------------------------------------------
# scsimgr set_attr -a escsi_log_dev=0xbc04b300

SEP

Re: scsi debugging

R.K. # — Thu, 13 Aug 2009 18:27:40 GMT

I have gone through man page of scsimgr which says that changes like enabling/disabling scsi object will log message in syslog.
Yes we suspect scsi issues for which I was asked to do this.

1. Is there any other file also that contains debug logs?

2. Is this correct command to enable scsi logging?
# scsimgr set_attr -a escsi_log_dev=0xbc04b300

3. And lastly, scsi debugging is done on device level ?

@SEP:
Once I get back to work, I will definitely try resarting syslogd.

Regds..

Re: scsi debugging

Matti_Kurkela — Thu, 13 Aug 2009 18:41:41 GMT

By default, the HP-UX syslog will ignore debug messages. You should adjust the /etc/syslog.conf configuration to log the debug messages (perhaps into a separate logfile), then send a kill -HUP to syslogd.

You may also want to add the "-v" option to syslogd (using /etc/rc.config.d/syslogd) and restart syslogd. This will add the facility/priority code to each log message. Being able to see the priority levels of each message will make it easier to further refine your syslog.conf configuration.

NOTE: when editing /etc/syslog.conf, remember to use TABs between message selectors and their associated log destinations, not spaces. See the man page of syslog for more information.

Re: scsi debugging

R.K. # — Sun, 16 Aug 2009 13:05:59 GMT

Thanks so far..

>>You should adjust the /etc/syslog.conf configuration to log the debug messages

Que 1: I am not sure on how to edit this file to enable the debugging. Need more help on this.

I have changed /etc/rc.config.d/syslogd from "-D" to "-D -v". Restarted syslogd. But still could NOT see any logging in syslog.

Que 2: How can I verify/test that logging is been done by system?

Re: scsi debugging

Bill Hassell — Sun, 16 Aug 2009 22:30:52 GMT

syslog logging is configured by the file /etc/syslog.conf. The /etc/rc.config.d file configures how syslogd is started and stopped.

-v turns on the facility and priority which will be useful later on. The change you need to make is in /etc/syslog.conf. Typically it looks like this:

mail.debug /var/adm/syslog/mail.log
*.info;mail.none /var/adm/syslog/syslog.log
*.alert /dev/console
*.alert root
*.emerg *

In this example, only mail messages will be logged all the way down to the debug level. Temporarily, you need to change the syslog.log line from *.info to *.debug. Now before you make the change, a very, very important rule: syslog.conf must have *NO* spaces between items. Any space in this file turns the line into a comment! (as far as I know, this is the only Unix command with this bizarre rule).

Secondly: once you make the change, open an extra window to monitor the size of syslog. The debug level can cause syslog.log to grow enormously fast (many MB in a few seconds) so you may need to switch back to *.info fairly quickly.

Now to prevent excessive syslog.log growth, you can redirect the scsimgr debug messages to a different file. To do this, you must first identify scsimgr messages in syslog with debug level set. Right after the date (when syslogd is run with -v), you'll see a 2 character code like 5B or 3D. This is the syslog sorting code -- numbers = priority or importance, letters = facility or category. Use the man page for syslog to find the character codes.

To redirect scsimgr debug messages to a different file, find the facility code (letters A through X) then edit the syslog.conf file. Suppose the scsimgr facility is LOCAL6 (letter = W) then syslog.conf should look like this:

*.info;mail.none;local6.none /var/adm/syslog/syslog.log
local6.debug /var/adm/scsimgr.log

This says: ignore all mail and all local6 messages for syslog.log, and send all messages for LOCAL6 to the file /var/adm/scsimgr.log file.

Now you can get the debug details without seeing a bunch of other service messages.

Re: scsi debugging

Bill Hassell — Sun, 16 Aug 2009 22:43:58 GMT

Almost forgot:

>How can I verify/test that logging is been done by system?

logger. This command can create a message at any priority and for any facility. Usage:

logger [-p facility.priority] "Some message"

So for LOCAL6 at a WARN level:

logger -p local6:warn "testing local6"

Then look in syslog.log (or scsimgr.log). Note also that any changes to syslog.conf must be followed by:

kill -HUP `cat /var/run/syslog.pid`

which will cause syslogd to re-reada the conf file.

Re: scsi debugging

R.K. # — Tue, 18 Aug 2009 00:21:07 GMT

Thanks a lot guys..!!

Will get back again in case I need more help.

Regds..

Re: scsi debugging

R.K. # — Sat, 22 Aug 2009 02:40:14 GMT

Hi Again,

I have changed *.info to *.debug and followed steps as said.

-Changed syslog.conf
-Made it verbose
-Restarted syslogd

BUT still I am not getting any debug messages logged into syslog.log.

Logger command is working fine.

Any suggestions....what could be the issue?

Thanks..

Re: scsi debugging

Bill Hassell — Sun, 23 Aug 2009 14:17:11 GMT

Are you getting the 2-char code right after the data in syslog (like 5D: or 6Q:). If not, syslogd isn't running with the -v option. If you are getting the 2-char code, do you see any "7" messages (ie, 7D or 7Q or 7B)? If not, then debug messages are not being logged. Make sure *.info was changed to exactly *.debug. Then use logger to generate a debug message:

logger -p local1.debug "testing local1.debug"

That should show the logger message with the code 7R:. If not, use:

logger -p local1.warn "testing local1.warn"

and that will log the message as 4R:

Re: scsi debugging

R.K. # — Mon, 24 Aug 2009 04:10:31 GMT

Hi Bill,

As you said, looks like I am getting normal outputs from logger command.

I have attached of what I did..please check.

But why am I not getting any debug messages from scsi device say a disk.

I am using below command for debugging a boot disk (just to see if it works):
# scsimgr set_attr -a escsi_log_dev=0xbc002003

I must be going wrong somewhere..
Totally confused..

Regds..

Re: scsi debugging

Bill Hassell — Mon, 24 Aug 2009 13:45:11 GMT

> Aug 23 21:49:36 7R:xxxxxxx root: testing local1.debug

The 7E: code indicates that everything is working with syslogd so the problem is with scsimgr. The manual doesn't mention anything about syslog debug at all:

http://docs.hp.com/en/scsimgr/scsimgr_whp_AR0709.pdf

The man page for scsimgr does mention the word debug one time for the option escsi_dbg_lvl.

Re: scsi debugging

R.K. # — Sat, 05 Sep 2009 20:12:38 GMT

Thanks a lot for your help..
Looks like something is wrong in devices I am trying to debug....will try it on different devices.

Regds..