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Speed up upgrades for a debian/ubuntu based system.
Please install aria2c before you try the above command. On ubuntu the command to install aria2c would be: $sudo aptitude install aria2

randomize hostname and mac address, force dhcp renew. (for anonymous networking)
this string of commands will release your dhcp address, change your mac address, generate a new random hostname and then get a new dhcp lease.

Scan a document to PDF
Adjust the --resolution and --mode as required (if these options are available for your scanner). The size options (-x, -y, -imageheight, -imagewidth) are for US letter paper. For A4, I think the command would be: $scanimage -p --resolution 250 --mode Gray -x 210 -y 297 | pnmtops -imageheight 11.7 -imagewidth 8.3 | ps2pdf - output.pdf

remove repeated pairs of characters e.g. "xtxtxtxt" will become "xt"
This will remove repeated characters e.g. echo "xtxtxtxt" | sed -ru 's/(..)\1{2,}/\1/g' the output will just be "xt"

Pretty print SQL query with python in one line
You need to apt-get install python-sqlparse. This command simply formats a sql query and prints it out. It is very useful when you want to move a sql query from commandline to a shell script. Everything is done locally, so you don't need to worry about copying sql query to external websites.

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

Find the package that installed a command

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

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

Silently ensures that a FS is mounted on the given mount point (checks if it's OK, otherwise unmount, create dir and mount)
In my example, the mount point is /media/mpdr1 and the FS is /dev/sdd1 /mountpoint-path = /media/mpdr1 filesystem=/dev/sdd1 Why this command ? Well, in fact, with some external devices I used to face some issues : during data transfer from the device to the internal drive, some errors occurred and the device was unmounted and remounted again in a different folder. In such situations, the command mountpoint gave a positive result even if the FS wasn't properly mounted, that's why I added the df part. And if the device is not properly mounted, the command tries to unmount, to create the folder (if it exists already it will also work) and finally mount the FS on the given mount point.


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