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How To Find Out If 32 or 64 bit Unix OS Installed On Server

I'm a new Unix system user. How can I determine if 32 or 64 bit OS is installed on my Unix server?
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HowTo: Check Swap Usage In Solaris Unix

How do I check swap (page) usage under Sun / Oracle Solaris Unix operating systems using command line options? How do I see virtual memory statistics including used and total swap space?
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Solaris UNIX: Display LUNs

How do I display LUNs under Solaris UNIX version 10 or earlier?
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UNIX / Linux Dump Command Exclude Directories / Files

I'm using dump command to backup file systems to tape and remote server. However, I'm not able to find any option that will allow me to exclude files or directories from backup. How do I force UNIX / Linux / FreeBSD dump command to exclude selected files (such as /var/cache or /usr/basejails) which I don't want to backup?
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How to: MySQL Delete Column

How do I delete a column from an existing MySQL table using UNIX / Windows / Linux mysql command line utility sql syntax?
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Examining the Linux / FreeBSD / UNIX filesystem with ls command

Q. I’m new to Linux and how do I examine filesystem and identify regular files or directories?

A. Both Linux and UNIX comes with ls command for examining the filesystem. You can use ls command to look at the filesystem. ls command can display:
=> Character devices
=> Regular files
=> Sym links (symbolic links)
=> Directories
=> Pipes
=> Sockets
=> Block devices

ls command examples

Display /etc directory files, enter:
$ ls /etc
When invoked without any arguments, ls lists the files in the current working directory:
$ ls
Use -l (long option) to lists filenames, sizes, permissions, type and all other information:
$ ls /etc/passwd

-rw-r--r-- 1 root root 2453 Jul 17 16:25 /etc/passwd

See Linux / UNIX file permissions for more information


A directory is marked with a d as the first letter of the permissions field:
ls -ld /etc

drwxr-xr-x 88 root root 12288 Aug  5 23:46 /etc

Symbolic link

A symbolic link is marked with an l (lower case L) as the first letter of the permissions string:
ls -l /bin/nisdomainname

lrwxrwxrwx 1 root root 8 Jul 10 08:50 /bin/nisdomainname -> hostname


  • A named pipe is marked with a p as the first letter of the permissions string.
  • A socket is marked with a s as the first letter of the permissions string.
  • A character device is marked with a c as the first letter of the permissions strings. (ls -l /dev/console)
  • A block device is marked with a b (ls -l /dev/sdb1).

MySQL Change a User Password

I would like to change a password for a user called tom using UNIX / Linux command line option. How do I change a user password under MySQL server?
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Linux / UNIX: Change File Permissions Recursively ( conditional )

How do I recursively change files with 777 permissions to 755 in /home/user/demo directory? I have a number of files in this directory and I need to change permission from 0777 to only if that file has 777 permissions. Is there an easy way out to achieve this on a Linux or Unix-like systems?
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lofiadm: Solaris Mount an ISO CD Image

Q. How do I mount an ISO CD image under Sun Solaris UNIX?
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