Here is what happens:
$ sudo visudo
>>> /etc/sudoers: syntax error near line 28 <<<
sudo: parse error in /etc/sudoers near line 28
sudo: no valid sudoers sources found, quitting
On a modern Ubuntu system (and many other GNU/Linux distributions), fixing a corrupted sudoers file is actually quite easy, and doesn’t require rebooting, using a live CD, or physical access to the machine.
To do this via SSH, log in to the machine and run the command pkexec visudo. If you have physical access to the machine, SSH is unnecessary; just open a Terminal window and run that pkexec command. Lire la suite…
Bash Shell Loop
How do I run shell loop over set of files stored in a current directory or specified directory?
You can use for loop easily over a set of shell file under bash or any other UNIX shell using wild card character.
Syntax
The general syntax is as follows:
for f in file1 file2 file3 file5
do
echo "Processing $f"
# do something on $f
done
You can also use shell variables:
FILES="file1
/path/to/file2
/etc/resolv.conf"
for f in $FILES
do
echo "Processing $f"
done
You can loop through all files such as *.c, enter:
$ for f in *.c; do echo "Processing $f file.."; done
Lire la suite…
Source: OpenVPN official documentation
OpenVPN daemons (JSON format):
./sacli VPNStatus
Show the number of users currently connected to the VPN:
./sacli VPNSummary
Show the status of internal Access Server services:
./sacli status
Stop internal Access Server services:
./sacli stop
Start/restart internal Access Server services:
./sacli start
The ‘start’ command is smart in the sense that if the Access Server
is already running, and you modified the configuration via
the Config DB, only those services whose parameters are changed
will be restarted. Note that if you modify any parameters in
the Access Server bootstrap configuration file
(/usr/local/openvpn_as/etc/as.conf), you will need to do a full unix
restart in order for those settings to take effect.
Also note that the start/stop commands above don’t actually start or
stop the Access Server daemon itself, only internal services
within the daemon. To start/stop the access server daemon itself,
use the traditional unix syntax:
Start the Access Server daemon:
/etc/init.d/openvpnas start
Stop the Access Server daemon:
/etc/init.d/openvpnas stop
Restart the Access Server daemon:
/etc/init.d/openvpnas restart
Terminal – Find Duplicate Files (based on size first, then MD5 hash)
find -not -empty -type f -printf "%s\n" | sort -rn | uniq -d | xargs -I{} -n1 find -type f -size {}c -print0 | xargs -0 md5sum | sort | uniq -w32 --all-repeated=separate
Find Duplicate Files (based on size first, then MD5 hash)
This dup finder saves time by comparing size first, then md5sum, it doesn’t delete anything, just lists them.
Terminal – Alternatives
find -type f -exec md5sum '{}' ';' | sort | uniq --all-repeated=separate -w 33 | cut -c 35-
Calculates md5 sum of files. sort (required for uniq to work). uniq based on only the hash. use cut ro remove the hash from the result.
find -type d -name ".svn" -prune -o -not -empty -type f -printf "%s\n" | sort -rn | uniq -d | xargs -I{} -n1 find -type d -name ".svn" -prune -o -type f -size {}c -print0 | xargs -0 md5sum | sort | uniq -w32 --all-repeated=separate
Improvement of the command « Find Duplicate Files (based on size first, then MD5 hash) » when searching for duplicate files in a directory containing a subversion working copy. This way the (multiple dupicates) in the meta-information directories are ignored.
Can easily be adopted for other VCS as well. For CVS i.e. change « .svn » into « .csv »:
find -type d -name ".csv" -prune -o -not -empty -type f -printf "%s\n" | sort -rn | uniq -d | xargs -I{} -n1 find -type d -name ".csv" -prune -o -type f -size {}c -print0 | xargs -0 md5sum | sort | uniq -w32 --all-repeated=separate
find -not -empty -type f -printf "%-30s'\t\"%h/%f\"\n" | sort -rn -t$'\t' | uniq -w30 -D | cut -f 2 -d $'\t' | xargs md5sum | sort | uniq -w32 --all-repeated=separate
Finds duplicates based on MD5 sum. Compares only files with the same size. Performance improvements on:
find -not -empty -type f -printf "%s\n" | sort -rn | uniq -d | xargs -I{} -n1 find -type f -size {}c -print0 | xargs -0 md5sum | sort | uniq -w32 --all-repeated=separateThe new version takes around 3 seconds where the old version took around 17 minutes. The bottle neck in the old command was the second find. It searches for the files with the specified file size. The new version keeps the file path and size from the beginning.
find . -type f -exec md5 '{}' ';' | sort | uniq -f 3 -d | sed -e "s/.*(\(.*\)).*/\1/"
This works on Mac OS X using the `md5` command instead of `md5sum`, which works similarly, but has a different output format. Note that this only prints the name of the duplicates, not the original file. This is handy because you can add `| xargs rm` to the end of the command to delete all the duplicates while leaving the original.
