Commands by leprasmurf (5)

  • I have come across multiple situations where I could only get to a server from a very restrictive bounce point which would not allow file transfers. I was able to uuencode a file, copy the output to a text file over putty, and then uudecode the file to transfer it. This works with any kind of file. Show Sample Output


    -4
    uuencode -m <filename> <filename>
    leprasmurf · 2009-12-22 15:28:59 0
  • Needed to get the Mac of various devices on a solaris box, but didn't have root. This command used awk to display the Network device, the IP, and the MAC a line at a time.


    1
    ifconfig -a | nawk 'BEGIN {FS=" "}{RS="\n"}{ if($1~ /:/) {printf "%s ", $1}}{ if($1=="inet") {print " -- ",system("arp "$2)}}'|egrep -v "^[0-9]$"
    leprasmurf · 2009-03-02 23:15:13 0
  • Telnet will make a tcp connection to a remote ip/port to test connectivity. If it times out, it's not reaching the host (maybe the firewall is blocking it). If connection is refused, it's reaching the host, but either the service is not listening on that port, or it's locked. Show Sample Output


    -2
    telnet <ip> <port>
    leprasmurf · 2009-02-12 19:11:03 2
  • Bash shortcut to work with the last argument of your last command Show Sample Output


    15
    file !$
    leprasmurf · 2009-02-06 15:41:08 2
  • Quick command to check if Perl library is installed on your server. Show Sample Output


    0
    perl -e "use SOAP::Lite"
    leprasmurf · 2009-02-06 15:26:37 0

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determine if tcp port is open

ptree equivalent in HP-UX
By setting the UNIX95 variable in HP-UX the XPG4 mode is activated, you get new options for ps and other commands, for me the best way to use this is to create an alias named ptree in root profile: alias ptree='UNIX95=1 ps -eH'

Show last changed files in a directory
This will quickly display files last changed in a directory, with the newest on top.

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Stream and copy a video from lan
Requires a listening port on HOST eg. "cat movie.mp4 | nc -l 1356 " (cat movie.mp4 | nc -l PORT) Useful if you're impatient and want to watch a movie immediately and download it at the same time without using extra bandwidth. You can't seek (it'll crash and kill the stream) but you can pause it.

Remount an already-mounted filesystem without unmounting it
Necessary for fsck for example. The remount functionality follows the standard way how the mount command works with options from fstab. It means the mount command doesn't read fstab (or mtab) only when a device and dir are fully specified. After this call all old mount options are replaced and arbitrary stuff from fstab is ignored, except the loop= option which is internally generated and maintained by the mount command. It does not change device or mount point.

Date shows dates at other times/dates
Use date to find the date at other days and times.

List all commands present on system
List all commands present on system by folder. $PATH contains all command folder separated by ':'. With ${PATH//:/ }, we change ':' in space and create a list of folder for ls command.

Append last argument to last command
Just like "!$", except it does it instantly. Then you can hit enter if you want.

Avoiding history file to be overwritten
If histappend options is set in bash, the file .bash_history will not be overwrite and history list is append to it.


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