$ script [file]

Run `script` command and a new shell starts up and records the input/output in the specified file until the shell is terminated.

To exit, `exit`.

If file is omitted, input/output are recorded in the file named 'typescript' in the current directory.

By default the log file is overwritten. If you want to append it, add the -a option.

I rebooted my server but fsck started forcibly on boot and it took long time until the system started.
To show or adjust fsck timing on ext2/ext3/ext4 filesystem, you can use tune2fs.

Show

# tune2fs -l /dev/sda1
・・・(omitted)
Mount count:              7
Maximum mount count:      27
Last checked:             Fri Oct 21 03:41:32 2011
Check interval:           15552000 (6 months)
Next check after:         Wed Apr 18 03:41:32 2012
・・・(omitted)

Stop forcible fsck

# tune2fs -c 0 -i 0 /dev/sda1 
tune2fs 1.39 (29-May-2006)
Setting maximal mount count to -1
Setting interval between checks to 0 seconds

Confirmation

# tune2fs -l /dev/sda1
・・・(omitted)
Mount count:              7
Maximum mount count:      -1
Last checked:             Fri Oct 21 03:41:32 2011
Check interval:           0 (<none>)
・・・(omitted)

Source: tune2fs でfsckを制御 - ike-daiの日記

-exec command {} \;

• Execute command after find. To pass results of find use {}.
• You must put a blank before "\;". If a blank is missing, an error occurrs like below.

  $ find . -name *~ -exec rm {}\;
  find: missing argument to `-exec'
  

  $ find . -name *~ -exec rm {}\;
  find: -exec: no terminating ";" or "+"
  

• To execute more than one command, specify multiple -exec.

Example:

find ~ -name '*bak' -exec rm {} \;

• In above example, "rm {} \;" following "-exec" is the command to execute. Last ";" denotes the end of the parameters. "\" before ";" is needed to escape "\" so that shell does not evaluate ";".

Example:

Delete all files whose name are *~ (Emacs backup file) in home directory.

$ find ~/ -name "*~" -exec rm {} \;

Delete all .svn directories from working directory tree of Subversion.

find . -name .svn -exec rm -rf {} \;

Grep files in directory tree.
（grep option -H for printing filename headers, -n for printing line number）

find <directory> -type f -exec grep -nH <pattern> {} \;

When you allow ftp with iptables, allowing port 21 like below is not enough to accept LIST command.

# iptables -A INPUT -p tcp --dport 21 -j ACCEPT

You need to load 2 modules ip_conntrack_ftp and ip_nat_ftp.
Edit /etc/sysconfig/iptables-config and add the following and they will be loaded automatically.

IPTABLES_MODULES="ip_conntrack_ftp ip_nat_ftp"

Then restart iptables.

# service iptables restart

Make sure the modules are loaded.

# lsmod
Module                  Size  Used by
nf_nat_ftp              7361  0 
nf_conntrack_ftp       13761  1 nf_nat_ftp
...(omit)

Source: iptablesでftpを通す

Use ssh -p option in rsync --rsh or -e option.

rsync --rsh="ssh -p 22222"

or

rsync -e "ssh -p 22222"

Source: rsync で ssh のポートを指定する方法 - METAREAL