Commands using tail (286)

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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

Colour part of your prompt red to indicate an error
If the return code from the last command was greater than zero, colour part of your prompt red. The commands give a prompt like this: [user current_directory]$ After an error, the "[user" part is automatically coloured red. Tested using bash on xterm and terminal. Place in your .bashrc or .bash_profile.

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" }

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

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

for x in `psql -e\l | awk '{print $1}'| egrep -v "(^List|^Name|\-\-\-\-\-|^\()"`; do pg_dump -C $x | gzip > /backups/$x-back.gz
Ran as the postgres user, dumps each database individually. It dumps with the create statements as well, so you can just 'zcat $x-nightly.dmp.gz | psql' to reimport/recreate a database from a backup.

rsync instead of scp
The command copies a file from remote SSH host on port 8322 with bandwidth limit 100KB/sec; --progress shows a progress bar --partial turns partial download on; thus, you can resume the process if something goes wrong --bwlimit limits bandwidth by specified KB/sec --ipv4 selects IPv4 as preferred I find it useful to create the following alias: alias myscp='rsync --progress --partial --rsh="ssh -p 8322" --bwlimit=100 --ipv4' in ~/.bash_aliases, ~/.bash_profile, ~/.bash_login or ~/.bashrc where appropriate.

Open Remote Desktop (RDP) from command line having a custom screen size
This example uses xfreerdp, which builds upon the development of rdesktop. This example usage will also send you the remote machine's sound.

Stat each file in a directory
Possible simplification of egrep-awk-sort with find and -exec with xargs.

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


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