Friday, March 11, 2005

Sun Solaris Command Tips

UNIX backups/Restore
Commands to take backup of /usr /var /lib directories to tape and disk using "tar"
a) tar -cvf /dev/rmt/0 /usr /var /lib [Taking into tape ]
b) tar -cvf backup_file.tar /usr /var /lib [ Taking disk image]
Taking backup to a tape device attached to a remote system
a) tar -cv /var /usr /lib | rsh remote_hostname dd of=/dev/rm/0 obs=128
b) ufsdump 0ucf remote_hostname:/dev/rmt/0 /file_system

Extracting / Restore the contents of a tape /tar file

a) tar -xvf /dev/rmt/0 [ restore contents of a tar tape ]
b) tar -xvf filename.tar [ Restore contents of a tar file ]
c) ufsrestore f /dev/rmt/0 filename [Restore from ufsdump tape backup]
d) ufsrestore rf remote_hostname:/dev/rmt/0 filename [ Restore from remote host tape device ]

List contents of backup

a) tar -tvf /dev/rmt/0 [ List contents of a tar tape ]
b) tar -tvf filename.tar [ List contents of a tar file ]
c) ufsrestore tf /dev/rmt/0n [ list contents of a tape of ufsdump]

Processes and Processor

What are the types of priority classes supported by Solaris ?
Timesharing, system and real-time

How will you place a running process in real time class?
priocntl -s –c RT –I uid process_id_number

How will you start a process in real time class?
priocntl –c RT –e process_name

How will you bind a process to processor ?
pbind –b processor_no process_id


What is the pocket size used by SQL*NET Version 2 on Solaris
Default is 2K

What is the procket size used by network layer TCP/IP in SQL*NET v2?
Default 1K

Inter process communication (IPC) tuning

What is post wait driver ?
The post wait driver reduces the overhead incurred by the more expensive use of
semaphore operation for interprocess communication.


What is the kernel parameter which controls the UNIX buffer cache on
solaris ?
bufhwm ( bufhwm is the maximum amount of physical memory, in kilobytes that can be used byI/O buffers)

While starting an oracle process , the unix system displays an erro message like "Cannot allocate more shared memory segment for the processes" If oracle person approaches you, how will you fix this problem?
ANS: increase the value for kernel memory parameter "set semsys:seminfo_semmns" in /etc/system file. [ this is a blind way]

System configurations

How do you find out total RAM installed on your machine
Ans: $prtconf |grep size

How do you find no. of processors installed on your sun box and processing speed?
Ans: $psrinfo –v

How do you find out how many disks are available on your system?
Ans: $ format (for sysadmins)
$ iostat –E (for users – count only the disks which has disk size correctly)

System Boot Options

How do you boot sun box in single user mode?
ANS: At ok prompt type "boot -s" [ ok boot -s OR ok boot -1 OR ok boot -S ]

What are the commands to shutdown the system?
ANS: shutdown, init , halt, reboot


What is the meaning of logical name of a disk drive format like c0t0d0s0?

ANS: c0 - Controller number
t0 - SCSI bus target number
d0 - Disk number
s0 - Partition or slice number
List some of the main device types?
ANS: /dev/dsk - Disk devices
/dev/rdsk - Raw or character devices
/dev/rmt - Tape devices
/dev/term - Serial line devices
/dev/pts - Pseudo terminals

List commands to display physical devices ?

ANS: prtconf



Note All commands are specific to Sun Solaris operating system


Ajay Kumar said...


This is test msg

Ajay Kumar

Anonymous said...

Hey! Apache is one of the most commonly used web servers out there. If you are running your own cPanel server your websites will actually run on Apache. If you're new to administering a web server thenred hatred hat