Run savecore -L on alternate dump device

Article:TECH124427  |  Created: 2010-01-16  |  Updated: 2011-07-12  |  Article URL http://www.symantec.com/docs/TECH124427
Article Type
Technical Solution

Product(s)

Environment

Issue



Run savecore -L on alternate dump device


Solution



'Savecore -L' can cause data corruption on /tmp and in swap on a system with or without an encapsulated root disk, as it will write over whatever the default is for 'savecore' as configured for 'dumpadm'. Do not run 'savecore -L' on a system with an encapsulated root disk with the default swap partition as a dump device. This procedure shows how to accomplish running the 'savecore -L' on an alternate dump device.
 
First capture the output from the command 'dumpadm' as this will be needed later when this configuration will need to be put this back into place after capturing the savecore -L output.
 
Example of what dumpadm looks like this:
 
# dumpadm
 
Dump content: kernel pages
 
Dump device: /dev/dsk/c1t0d0s1 (swap)
 
Savecore directory: /var/crash/sprst1000a0-14.spr.spt.symantec.com
 
Savecore enabled: yes
 
The procedure for creating the alternate dump device, and running 'savecore -L':
 
1. Make a dump directory
 
# mkdir /dumpdev
 
2. Now direct dumpadm to this new directory.
 
# dumpadm -s /dumpdevice
 
3. Pick out a unused disk - not in use by a diskgroup, and NOT the root device.
 
4. Run 'dumpadm -d' on the block device from step 3.
 
Example:
 
# dumpadm -d /dev/dsk/c0t50060E80104EF3F2d12s2
 
5. Now run 'savecore -L' on the /dumpdev
 
Example:
 
# savecore -L /dumpdev
 
This will populate the /dumpdev with the following, which is what will be needed from the 'savecore -L'
 
Example
 
# ls -l /dumpdevice
 
total 706498
 
-rw-r--r-- 1 root root 2 Mar 16 12:49 bounds
 
-rw-r--r-- 1 root root 2538097 Mar 16 12:49 unix.0
 
-rw-r--r-- 1 root root 358989824 Mar 16 12:49 vmcore.0
 
6. Tar these up, gzip, and upload to ftp.veritas.com:
 
FTP the resulting compressed file to ftp.veritas.com
 
Username: symsupport
Password: iS*pp8rT1
ftp> cd /incoming
 
ftp>bin --to change to binary transfer mode
 
ftp> put <file>
 
7. Email the TSE via case to inform that the data has been uploaded for analysis.
 

 
To put the dumpadm back:
 
*1. Re-direct the dump device back to original configuration
 
# dumpadm -d /dev/dsk/c1t0d0s1
 
2. Put configuration back for kernel dump.
 
# dumpadm -u
 
*3. Modify dump configuration back to the path it was originally set for.
 
# dumpadm -s /var/crash/sprst1000a0-14.spr.spt.symantec.com
 
* Please use the output from the system dumpadm before doing the procedure for these.
 
This is what it should look like after putting it back into place:
 
Example:
 
# dumpadm
 
Dump content: kernel pages
 
Dump device: /dev/dsk/c1t0d0s1 (swap)
 
Savecore directory: /var/crash/sprst1000a0-14.spr.spt.symantec.com
 
Savecore enabled: yes
 

 


Legacy ID



347413


Article URL http://www.symantec.com/docs/TECH124427


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