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It's useful mostly for your custom scripts, which running on specific host and tired on ssh'ing every time when you need one simple command (i use it for update remote apt repository, when new package have to be downloaded from another host).
Don't forget to set up authorization by keys, for maximum comfort.
I simply find binary notation more straightforward to use than octal in this case.
Obviously it is overkill if you just 600 or 700 all of your files...
Creates the .ssh directory on the remote host with proper permissions, if it doesnt exist. Appends your public key to authorized_keys, and verifies it has proper permissions. (if it didnt exist it may have been created with undesireable permissions).
*Korn shell syntax, may or may not work with bash
If you make a mess (like I did) and you removed all the executable permissions of a directory (or you set executable permissions to everything) this can help.
It supports spaces and other special characters in the file paths, but it will work only in bash, GNU find and GNU egrep.
You can complement it with these two commands:
1. add executable permission to directories:
find . type d -print0 | xargs -0 chmod +x
2. and remove to files:
find . type d -print0 | xargs -0 chmod -x
Or, in the same loop:
while IFS= read -r -u3 -d $'\0' file; do
case $(file "$file" | cut -f 2- -d :) in
:*executable*|*ELF*|*directory*)
chmod +x "$file"
;;
*)
chmod -x "$file"
;;
esac || break
done 3< <(find . -print0)
Ideas stolen from Greg's wiki: http://mywiki.wooledge.org/BashFAQ/020
Usage: VBoxBlockBoot [Virtual_Machine] [Block_device]
Eg: VBoxBlockBoot WinXP /dev/sdc
In another words
vm=usb; usb=sdc;sudo umount /dev/$usb* ; sudo chmod 777 /dev/$usb ; VBoxManage storageattach $vm --medium ~/raw-HD-4-VB/$usb.vmdk --type hdd --storagectl "IDE Controller" --device 0 --port 0 ; VBoxManage startvm $vm
Where
vm --> Name of the virtual machine to start
usb --> Block device to use. (/dev/sdc)
This can used after setup up a boot loader on to my USB pen drive or HDD (After creating Live USB). Here root privilege is needed but not granted to Virtual Box. Thus we can access all our VM.( If we run VBox as root we can't access our VMs). Root privilege is used to
- Unmount the storage device
- Chmod to full access (777)
Requirements:-
1. Device information file (rawvmdk file) created by the following command. Need to run only once. Not bad to run many.
VBoxCreateRawDisk() { VBoxManage internalcommands createrawvmdk -filename ~/.rawHD4VB_`basename "$1"`.vmdk -rawdisk "$1"; }
2. Root privilege to umount & chmod
3. Real storage medium (ie /dev/*) (Non-virtual such as USB HD, pen drive, a partition)
4. A virtual m/c already available (here "usb")
vm=usb; usb=sdc;sudo umount /dev/$usb* ; sudo chmod 777 /dev/$usb ; VBoxManage storageattach $vm --medium ~/raw-HD-4-VB/$usb.vmdk --type hdd --storagectl "IDE Controller" --device 0 --port 0 ; VBoxManage startvm $vm
VBoxBlockBoot() { sudo umount "$2"*; sudo chmod 777 "$2"; VBoxManage storageattach "$1" --medium ~/.rawHD4VB_`basename "$2"`.vmdk --type hdd --storagectl "IDE Controller" --device 0 --port 0 ; VBoxManage startvm "$1"; }
+ at the end means that many filenames will be passed to every chmod call, thus making it faster. And find own {} makes sure that it will work with spaces and other characters in filenames.
Command uses find to find and chmod all files recursively.
This will create, in the current directory, a file called 'pk.pem' containing an unencrypted 2048-bit RSA private key and a file called 'cert.pem' containing a certificate signed by 'pk.pem'. The private key file will have mode 600.
!!ATTENTION!! ==> this command will overwrite both files if present.
The first argument is the interpreter for your script, the second argument is the name of the script to create.
A few characters shorter that the other command
I often use it at my work, on an ovh server with root ssh access and often have to change mod after having finished an operation.
This command, replace the user, group and mod by the one required by apache to work.
a simple command in order to make iptables rules permanent, run @ sudo!
Quick and dirty way to disable the Ubuntu notifications that can be quite annoying. It prevent the notify-osd to start so you need to logout Gnome or kill it by hand to take effect.
Listens for events in the directory. Each created file is displayed on stdout. Then each fileline is read by the loop and a command is run.
This can be used to force permissions in a directory, as an alternative for umask.
More details:
http://en.positon.org/post/A-solution-to-the-umask-problem%3A-inotify-to-force-permissions
This will handle the case that the filename has spaces or other characters that need to be escaped.
Reconstruct standard permissions for directories and files in current directory