If you are looking for a lightweight, lean&mean operating system oriented towards web applications, then download and play with Peppermint Linux. It has just been released in the last few days.
http://peppermintos.com/
Archive for the ‘ Linux ’ Category
Superfast distro out there
Author: danielMay 12
Configuring proftpd behind NAT
Author: danielMay 9
If your ftp server is behind a NAT router, the regular ftps configuration steps you find in most tutorials in the Internet may not work for you. Hope these steps help.
1. Chroot (chain or jail) users to their home directory by adding the line below to proftpd.conf
DefaultRoot ~
2. Generate certificate keys, in this case, in the directory /etc/proftpd/ssl/
$openssl req -new -x509 -days 365 -nodes -out /etc/proftpd/ssl/server.cert.pem -keyout /etc/proftpd/ssl/server.key.pem
3. Add this lines to proftpd.conf
TLSEngine on TLSLog /var/log/proftpd/tls.log TLSProtocol SSLv23 TLSOptions NoCertRequest TLSRSACertificateFile /etc/proftpd/ssl/proftpd.cert.pem TLSRSACertificateKeyFile /etc/proftpd/ssl/proftpd.key.pem TLSVerifyClient off TLSRequired on
4. Allow a range of passive ports to be forwarded to your ftp server by the firewall and set those ports in your ftp config file – proftpd.conf in this case.
PassivePorts 60000 60100
5. Masquerade the ftp server’s address to the external IP of the NAT server/router.
MasqueradeAddress x.x.x.x
Sys admins – keep an eye on this.
Author: danielMay 7
Got this advice from a CTO – hot topics for system administrators:
1. performance monitoring
2. capacity planning
3. virtualization
4. Disaster recovery(DR) planning
Redirecting php error message to a log file
Author: danielMay 7
By default, any error message in your php script will be visible to site visitors on the browser and will be logged to apache error log file – most commonly in “/var/log/httpd/error.log”. In a production server it is advisable to prevent the error message from appearing on browser and has to be silently sent to a custom log file, specifically created for logging only php error messages. Following these steps might help:
1. Create the file under /var/log –
$touch /var/log/php-error.log
2. change permission to 644 –
$chmod 644 /var/log/php-error.log
3. set ownership –
$chown root.apache /var/log/php-error.log
(if httpd is running under apache, could be www-data, nobody…)
4. Edit /etc/php.ini and make sure the following options are set correctly
error_reporting = E_ALL display_errors = OFF error_log =/var/log/php-error.log log_errors = ON
5. Write a php script with some syntax error in it and check whether the error notification is logged or not
$tail -f /var/log/php-error.log
Changing passphrase of a private key
Author: danielMay 5
It is not advisable to use password based login for ssh any more. One of the most secure ways of remote login through ssh is to use public key authentication. But in order to do that you have to generate both private and public keys using ssh-keygen, for RSA the default file names would be id_rsa (private key) and id_rsa.pub (public key). Since you have already generate those keys with a passphrase and want to change the passphrase now, execute the following command:
$ ssh-keygen -f id_rsa -p
type your new passphrase, you are done!
Booting linux in single user mode
Author: danielMay 2
Have you locked yourself out of your linux machine? If by any chance you forgot the root password of your linux box and you have physical access to that machine, booting linux in single user mode will do the trick. Restart your computer using one of the following commands:
$shutdown -r now
OR
$init 6
OR
$reboot
Then select the Linux kernel from the boot menu, type “e” (for edit). Then select the second line which starts with the word “kernel” and type “e”. Then press “space bar” and type “single” (for linux single user mode). Finally press “Enter” and type “b” for boot. Go ahead change the password now with
$passwd