Commands by alf

Commands by alf (5)

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Untar a directory in a tar file over ssh

This may be listed already but this command is useful to untar a specific directory to a different server.
This is sample output - yours may be different.
0

cat tarfile.tar.gz | ssh server.com " cd /tmp; tar xvzf - directory/i/want"

alf · 2011-02-11 17:10:01 1
Automatd ssh public key setup without ssh-copy-id

Some servers don't have ssh-copy-id, this works in those cases. It will ask for the destination server, this can be IP, hostname, or [email protected] if different from current user. Ssh keygen will let you know if a pubkey already exists on your system and you can opt to not overwrite it.
This is sample output - yours may be different.
-2

echo 'Host or [email protected]?:'; read newserver && ssh-keygen -N "" -t rsa -f ~/.ssh/id_rsa ; ssh $newserver cat <~/.ssh/id_rsa.pub ">>" ~/.ssh/authorized_keys ; ssh $newserver

alf · 2010-05-07 06:24:53 1
Show interface/ip using awk

Interfaces like lo can be omitted from the beginning, there are probably better ways of doing this, i'm a noob at awk. Show Sample Output
This is sample output - yours may be different.
```
lo 127.0.0.1
wlan0 192.168.1.100
```
5

ifconfig -a| awk '/^wlan|^eth|^lo/ {;a=$1;FS=":"; nextline=NR+1; next}{ if (NR==nextline) { split($2,b," ")}{ if ($2 ~ /[0-9]\./) {print a,b[1]}; FS=" "}}'

alf · 2010-04-15 04:34:28 3
Update zone file Serial numbers

Will edit *.db files in the same directory with todays date. Useful for doing a mass update to domains on a nameserver, adding spf records, etc. Looks for a string starting with 200 or 201 followed by 7 numbers, and replaces with todays date. This won't overwrite Ip's but i would still do some double checking after running this. Make sure your server's date is correct, otherwise insert your own serial number. rndc reload should usually follow this command.
This is sample output - yours may be different.
7

sed -i 's/20[0-1][0-9]\{7\}/'`date +%Y%m%d%I`'/g' *.db

alf · 2010-03-24 07:28:58 3
Use ping to test if a server is up

Bash scrip to test if a server is up, you can use this before wget'ing a file to make sure a blank one isn't downloaded.
This is sample output - yours may be different.
-1

if [ "$(ping -q -c1 google.com)" ];then wget -mnd -q http://www.google.com/intl/en_ALL/images/logo.gif ;fi

alf · 2010-03-23 04:15:03 7

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Jump to a directory, execute a command and jump back to current dir

Display Spinner while waiting for some process to finish

alternatively, run the spinner for 5 seconds: timeout 5 bash -c 'spinner=( Ooooo oOooo ooOoo oooOo ooooO oooOo ooOoo oOooo); while true; do for i in ${spinner[@]}; do for j in seq 0 ${#i}; do echo -en "\b\b"; done; echo -ne "${i}"; sleep 0.2; done; done'

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"

Mirror the NASA Astronomy Picture of the Day Archive

Mirror the entire NASA Astronomy Picture of the Day archive, all the way from 1995. The archive is close to 2.5 GB, with lots of files, so give it some time. The logs can be redirected to a file using '-o somefile'. You might also want to try '-nH' and the '--cut-dirs' options

check open ports without netstat or lsof

Extract title from HTML files

previous version leaves lots of blank lines

Make changes in .bashrc immediately available

You may want to just use the shortcut "." instead of "source"

Convert CSV to JSON

Replace 'csv_file.csv' with your filename.

Get mouse location (X,Y coordinates)

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

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Commands by alf (5)

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