Using SCP is a great way to transfer files from one machine to another. SCP uses SSH and can move files to/from localhost remotehost or remotehost remotehost.
SCP Syntax: localhost -> remotehost

scp /path/to/source-file user@host:/path/to/destination-file

SCP Syntax: remotehost -> remotehost

scp user@src-host:/path/to/src-file user@dest-host:/path/to/dest-file

SCP Examples

scp file.txt mydomain.com:~/mydir/file.txt
 
scp local_dir/filename myname@host1:remote_dir
 
scp local_dir/* myname@host1:remote_dir
 
scp myname@host1:remote_dir/filename .
 
scp myname@host1:remote_dir/filename myname@host2:another_dir

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To sync your linux server’s time with the NTP Pool Time Servers, use the following command.

ntpdate pool.ntp.org

If you’d like to sync with a time server weekly, add a new file named ntpdate-sync to /etc/cron.weekly. Then set the file permissions to 755 and set owner:group to root:root. Finally, exit set the file contents to [...]

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To “branch” or “tag” within a repository, use svn copy. The syntax is simple.

svn copy {SRC} {DST}

The source and destination can be either a working copy path or full URL in any combination. So to tag a revision from trunk the following command could be used.

svn copy –username myusername –password mypassword http://domain.com/svn/trunk http://domain.com/svn/tag/0.1.1332 [...]

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Step 1 – At the linux shell, stop the current mysqld process, start the mysqld_safe process with –skip-grant-tables switch and login as root (no password).

/etc/init.d/mysql stop
mysqld_safe –skip-grant-tables &
mysql -u root

Step 2 – At the mysql shell set the root password and flush privileges.

USE mysql;
UPDATE user SET password=PASSWORD("new-password-here") WHERE User=’root’;
FLUSH PRIVILEGES;
QUIT;

Step 3 – Back at the [...]

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To reset the MySQL root password, login to the mysql shell and run the following commands.

SET PASSWORD FOR root@localhost=PASSWORD(’RootPasswordHere’);
FLUSH PRIVILEGES;

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To grant all privileges to a user from any location login to the mysql shell and run the following queries.

GRANT ALL PRIVILEGES ON *.* TO username@localhost IDENTIFIED BY ‘PasswordHere’ WITH GRANT OPTION;
GRANT ALL PRIVILEGES ON *.* TO username@"%" IDENTIFIED BY ‘PasswordHere’ WITH GRANT OPTION;
FLUSH PRIVILEGES;

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Use Apache’s mod_expires to explicitly set the expiration of a file by it’s type. This will enable to browser to cache these static assets and greatly increase performance.

<IfModule mod_expires.c>
ExpiresActive on
ExpiresDefault "now"
ExpiresByType text/html "now"
ExpiresByType text/xml "now"
[...]

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Prerequisites

First make sure that you are able to login to the remote host using ssh key authentication.

Basic Syntax

To sync files from a local directory to a remote directory use the following syntax:

rsync {options} -e ssh {source} {dest}

Example

Here is an example that exclude all .psd and .fla files:

rsync –exclude *.psd \
[...]

Filed under: System Administration, linux, rsync, ssh | 2 Comments

Create and Compress and Archive
Archive a group of files:

tar -czvf archive.tar.gz file1 file2 file3

Archive an entire directory:

tar -czvf archive.tar.gz directory/

Extract a Compressed Archive

tar -xzvf archive.tar.gz

List the Contents of a Compressed Archive

tar -tzvf archive.tar.gz

Common tar Switches

-c create a new archive
-x extract files from an archive
-t list the contents of an archive
-z filter the archive through gzip
-v [...]

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Step 1: Generate Keypair on Localmachine

ssh-keygen -t dsa

When prompted for a passphrase you can leave it empty to enable logging in without a password (please note that there are potential security issues with doing this).

After confirming your passphrase at the second prompt you’ll find two new files (the keypair) in your ~/.ssh directory. The [...]

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