Viewing System Messages

System messages display on the console device. The text of most system messages look like this:

[ID msgid facility.priority]

For example:

[ID 672855 kern.notice] syncing file systems...

If the message originated in the kernel, the kernel module name is displayed. For example:

Oct 1 14:07:24 mars ufs: [ID 845546 kern.notice] alloc: /: file system full 

When a system crashes, it may display a message on the system console like this:

panic: error message

where error message is one of the panic error messages described in crash(1M).

Less frequently, this message may be displayed instead of the panic message:

Watchdog reset !

The error logging daemon, syslogd, automatically records various system warnings and errors in message files. By default, many of these system messages are displayed on the system console and are stored in the /var/adm directory. You can direct where these messages are stored by setting up system logging. See "How to Customize System Message Logging" for more information. These messages can alert you to system problems, such as a device that is about to fail.

The /var/adm directory contains several message files. The most recent messages are in /var/adm/messages (and in messages.0), and the oldest are in messages.3. After a period of time (usually every ten days), a new messages file is created. The messages.0 file is renamed messages.1, messages.1 is renamed messages.2, and messages.2 is renamed messages.3. The current /var/adm/messages.3 is deleted.

Because /var/adm stores large files containing messages, crash dumps, and other data, this directory can consume lots of disk space. To keep the /var/adm directory from growing too large, and to ensure that future crash dumps can be saved, you should remove unneeded files periodically. You can automate this task by using crontab. See "How to Delete Crash Dump Files" and Chapter 30, Scheduling System Events (Tasks) for more information on automating this task.

How to View System Messages

Display recent messages generated by a system crash or reboot by using the dmesg command.

$ dmesg

Or use the more command to display one screen of messages at a time.

$ more /var/adm/messages

For more information, refer to dmesg(1M).

Example--Viewing System Messages

The following example shows output from the dmesg command.

$ dmesg
date starbug genunix: [ID 540533 kern.notice] SunOS Release 5.8 Version 64-bit
date starbug genunix: [ID 223299 kern.notice] Copyright (c) 1983-1999 by Sun Microsystems, Inc.
date starbug genunix: [ID 678236 kern.info] Ethernet address = xx:xx:xx:xx:xx:xx
date starbug unix: [ID 389951 kern.info] mem = 131072K (0x8000000)
date starbug unix: [ID 930857 kern.info] avail mem = 122134528
date starbug rootnex: [ID 466748 kern.info] root nexus = Sun Ultra 5/10 UPA/PCI (UltraSPARC-IIi 333MHz)
date starbug rootnex: [ID 349649 kern.info] pcipsy0 at root: UPA 0x1f 0x0
date starbug genunix: [ID 936769 kern.info] pcipsy0 is /pci@1f,0
date starbug pcipsy: [ID 370704 kern.info] PCI-device: pci@1,1, simba0
date starbug genunix: [ID 936769 kern.info] simba0 is /pci@1f,0/pci@1,1
date starbug pcipsy: [ID 370704 kern.info] PCI-device: pci@1, simba1
date starbug genunix: [ID 936769 kern.info] simba1 is /pci@1f,0/pci@1
date starbug simba: [ID 370704 kern.info] PCI-device: ide@3, uata0
date starbug genunix: [ID 936769 kern.info] uata0 is /pci@1f,0/pci@1,1/ide@3
.
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