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Check a nfs mountpoint and force a remount if it does not reply after a given timeout.
Based on the execute with timeout command in this site. A more complex script: #!/bin/sh # This script will check the avaliability of a list of NFS mount point, # forcing a remount of those that do not respond in 5 seconds. # # It basically does this: # NFSPATH=/mountpoint TIMEOUT=5; perl -e "alarm $TIMEOUT; exec @ARGV" "test -d $NFSPATH" || (umount -fl $NFSPATH; mount $NFSPATH) # TIMEOUT=5 SCRIPT_NAME=$(basename $0) for i in $@; do echo "Checking $i..." if ! perl -e "alarm $TIMEOUT; exec @ARGV" "test -d $i" > /dev/null 2>&1; then echo "$SCRIPT_NAME: $i is failing with retcode $?."1>&2 echo "$SCRIPT_NAME: Submmiting umount -fl $i" 1>&2 umount -fl $i; echo "$SCRIPT_NAME: Submmiting mount $i" 1>&2 mount $i; fi done

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Check Ram Speed and Type in Linux
from http://maysayadkaba.blogspot.com/2008/08/linux-check-ram-speed-and-type.html

Update grub menu.lst
Remove all commented lines Remove all blank lines Show the menu Up the delay so you have enough time to select a kernel Remove the quiet so you can watch the entire boot Add a rootdelay for san attached storage booting

Install pip with Proxy
Installs pip packages defining a proxy

set prompt and terminal title to display hostname, user ID and pwd
used in an if-then-else in case the default shell is ksh, not bash. The $(basename ${0#-}) is handy to echo which shell and strip the dash some flavors put in front of "bash" if [ $(basename ${0#-}) == "bash" ] ; then export PS1='\[\e]0;\h \u \w\a\]\n\[\e[0;34m\]\u@\h \[\e[33m\]\w\[\e[0;32m\]\n\$ ' else HOST=`hostname` ESC=`echo "\033"` BEL=`echo "\007"` RAW=`echo "\r"` export PS1='-${RAW}${ESC}]0;${HOST} ${USER}${BEL}-${ESC}[0;34m${USER}${ESC}[0m@${ESC}[0;34m${HOST%%.*}${ESC}[0;33m${ESC}[0m $ ' fi

force a rescan on a host of scsi devices (useful for adding partitions to vmware on the fly)

Determining the excat memory usages by certain PID
this command gives you the total number of memory usuage and open files by the perticuler PID.

list block devices
Shows all block devices in a tree with descruptions of what they are.

Quick access to the ascii table.


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