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Per default, linux/unix shells are configured with a width of 80 characters.
If you like to edit a phrase or string on a line with more than 80 characters it might take long to go there (for example a line with 1000 characters and you like to edit the 98th word which is character 598-603).
Maybe you might wish to use 78 characters, because if you forward the text via mail and the text will be quoted (2 extra characters at the beginning to the line "> "), you use 80 characters, otherwise 82, which are lame.
Create a exact mirror of the local folder "/root/files", on remote server 'remote_server' using SSH command (listening on port 22)
(all files & folders on destination server/folder will be deleted)
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
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"
Replace 'csv_file.csv' with your filename.
bs = buffer size (basically defined the size of a "unit" used by count and skip)
count = the number of buffers to copy (16m * 32 = 1/2 gig)
skip = (32 * 2) we are grabbing piece 3...which means 2 have already been written so skip (2 * count)
i will edit this later if i can to make this all more understandable
The command is useful when, e.g., booting an existing system with a rescue or installation CD where you need to chroot into the hard-disk and be able to do stuff which accesses kernel info (e.g. when installing Ubuntu desktop with LVM2 you need to mount and chroot the hard disk from a shell window in order to install packages and run initramfs inside chroot).
The command assumes that /mnt/xxx is where the chroot'ed environment's root file system on the hard disk is mounted.