Commands by lv4tech

Commands by lv4tech (10)

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Get acurate memory usage of a Process in MegaBytes
This is sample output - yours may be different.
1

pmap $(pgrep [ProcessName] -n) | gawk '/total/ { a=strtonum($2); b=int(a/1024); printf b};'

lv4tech · 2010-04-28 08:16:28 4
Test file system performance

You need bonnie++ package for this. More detail than a simple hdparm -t /dev/sda would give you. the -d is the directory where it performs writes/reads for example I use /tmp/scratch with 777 permissions Bonnie++ benchmarks three things: data read and write speed, number of seeks that can be performed per second, and number of file metadata operations that can be performed per second.
This is sample output - yours may be different.
6

bonnie++ -n 0 -u 0 -r <physical RAM> -s <2 x physical ram> -f -b -d <mounted disck>

lv4tech · 2009-09-18 09:46:44 10
display portion of a file

This is useful for displaying a portion of a FILE that contains an error at line NUMBER
This is sample output - yours may be different.
-1

cat -n FILE | grep -C3 "^[[:blank:]]\{1,5\}NUMBER[[:blank:]]"

lv4tech · 2009-05-17 18:19:55 8
List all PostgreSQL databases. Useful when doing backups
This is sample output - yours may be different.
3

psql -U postgres -lAt | gawk -F\| '$1 !~ /^template/ && $1 !~ /^postgres/ && NF > 1 {print $1}'

lv4tech · 2009-05-15 14:33:50 6
Get your public ip using dyndns
This is sample output - yours may be different.
17

curl -s http://checkip.dyndns.org/ | grep -o "[[:digit:].]\+"

lv4tech · 2009-05-14 09:43:31 15
List all system users
This is sample output - yours may be different.
-9

~<press tab twice>

lv4tech · 2009-05-12 17:33:33 12
Generate padded numbers 001 002 ... 100
This is sample output - yours may be different.
0

echo 00{1..9} 0{10..99} 100

lv4tech · 2009-05-07 21:08:53 10
Search for files older than 30 days in a directory and list only their names not the full path
This is sample output - yours may be different.
2

find /var/www/html/ -type f -mtime +30 -exec basename {} \;

lv4tech · 2009-05-07 21:05:47 6
Find out which version of linux you are running
This is sample output - yours may be different.
-6

cat /etc/*issue

lv4tech · 2009-05-07 20:53:03 10
Cloning hard disks over the network:

This is a bit to bit copy so if you have a 500GB hard disk it will take a long time even if have Gigabit Ethernet
This is sample output - yours may be different.
-1

Boot up destination machine with Knoppix live CD and run nc -l -p 9000 | dd of=/dev/sda Then on the master dd if=/dev/sda | nc <dest-ip> 9000 You can monitor bandwidth usage to see progress: nload eth0 -u M

lv4tech · 2009-05-07 05:26:58 6

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tcpdump sniff pop3,imap,smtp and http

Generate a Change Log with git

Generate a changelog between the v1 and v2 tags

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"

Fire CMD every time FILE (or directory) is updated (on *BSD)

Find the package that installed a command

Create a .png from a command output and upload to ompdlr.org, give URI

Create a .png from output command or whatever, the upload and give URI from ompdlr.org

geoip information

That makes a function you can put in your ~/.bashrc to run it when you need in any term with an IP as argument

Decode a MIME message

will decode a mime message. usefull when you receive some email and file attachment that cant be read.

Get AWS temporary credentials ready to export based on a MFA virtual appliance

You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Convert PDF to JPG

Without the bashisms and unnecessary sed dependency. Substitutions quoted so that filenames with whitespace will be handled correctly.

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