Sunday, 24 June 2012

How to Enable TUN/TAP Module in OpenVZ

OpenVZ supports VPN inside a container via kernel TUN/TAP module and device. To allow VPS #101 to use the TUN/TAP device the following should be done: 

#101 - VPS  id. Replace #101 with your VPS id.

Make sure the tun module has already loaded on the Node.
[root@Node /]#  lsmod | grep tun

If not listed, then load the tun module with the below command
[root@Node /]# modprobe tun

 [root@Node /]#  lsmod | grep tun
  tun                    82432  6

Run the following command in Node:
[root@Node /]#  vzctl set 101 --devnodes net/tun:rw --save
[root@Node /]#  vzctl set 101 --devices c:10:200:rw --save 
[root@Node /]#  vzctl stop 101 
[root@Node /]#  vzctl set 101 --capability net_admin:on --save
[root@Node /]#  vzctl start 101 
[root@Node /]#  vzctl exec 101 mkdir -p /dev/net
[root@Node /]#  vzctl exec 101 chmod 600 /dev/net/tun 

To check TUN/TAP is enabled or not :
[root@Node /]# vzctl enter 101
 
Inside the VPS: 
[root@vps /]# cat /dev/net/tun
cat: /dev/net/tun: File descriptor in bad state     # It means the TUN/TAP is enabled on your VPS.
 
 cat: /dev/net/tun: No such device     #  If you receive like this, then the TUN/TAP has not enabled on your VPS . Try to enable TUN/TAP again and check.
 

Source: http://wiki.openvz.org/VPN_via_the_TUN/TAP_device

Saturday, 23 June 2012

Error: -bash: mail: command not found in CentOS

You may get this error while trying to send mail from ssh. It means the package is not installed. Try to send mail after installing the package " mailx"


[root@test ~]# mail -v testmail@example.com

-bash: mail: command not found



Fix: # yum install mailx



Thursday, 9 February 2012

How to Reset the Login Password for DirectAdmin Control Panel

If you forget the password for DirectAdmin, then follow the steps to reset your password.

check the setup.txt file for password.
[root@test]# cat /usr/local/directadmin/scripts/setup.txt

if the password in the setup.txt  not works, then try to change the admin password with the following command,
[root@test]# passwd admin
Changing password for user admin.
New UNIX password:
Retype new UNIX password:
passwd: all authentication tokens updated successfully.


Friday, 3 February 2012

SMTP Error: No support for Delivery Status Notifications

You may get the SMTP Error while trying to send emails from webmail roundcube. This error occurs because the new version of roundcube uses a feature that our servers do not have available (due to incompatibility server e-mails) and the lack of this feature is shown the error message and the email is not sent.



Fix:
 # Go to settings option then click composing messages and uncheck it as in the below picture.
    Then save it and now try to send emails. Now you can send mails !!