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Enable TUN/TAP and PPD in VM on open VZ

How to enable TUN/TAP and PPD in VM on open VZ

Please use the below steps to Enable TUN/TAP and PPD in VM on open VZ.

   1.Check the Node is enabled with tun/tap by entering the same from
   >> Go to list node >> edit node >> check "Allow clients to set TUN/TAP"
and "Allow clients to set PPP".
   2.How to enable TUN/TAP in OpenVZ?
STEP 1: Login to Node via SSH
STEP 2: Run the below pasted command to find out tun module is already loaded
or not

[root@Node]# lsmod | grep tun
  If the output of the above commands returns a blank value means the tun
module is not loaded in your Node.
Run the below command to load tum module.

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

  3. Enabling TUN/TAP on VPS
vi /etc/sysconfig/vz-scripts/(VMID)4349.conf

Add the following in bottom of the file.

DEVNODES="net/tun:rw "

Allow the container to use the tun/tap device by running the following
commands on the host node:

[root@Node]# vzctl set 101(VMID) --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

4. To check whether the tun tap is enabled please login to VPS and check the
following command

cat: /dev/net/tun: File descriptor in bad state     # It means the TUN/TAP is
enabled on your VPS.


3. Enabling pppd


HN#  (Go to host node )

   modprobe tun

   modprobe ppp-compress-18

   modprobe ppp_mppe

   modprobe ppp_deflate

   modprobe ppp_async
modprobe pppoatm

   modprobe ppp_generic

4. Stop the VM

   # vzctl stop {VEID}

5. From HN, run the below commands:


   # vzctl set {VEID} --features ppp:on --save

   # vzctl start {VEID}

   # vzctl set {VEID} --devices c:108:0:rw --save

   # vzctl exec {VEID} mknod /dev/ppp c 108 0

   # vzctl exec {VEID} chmod 600 /dev/ppp

6. Login to VE and see if the 'pppd' command works.


   # /usr/sbin/pppd
If you see some garbage values, it means it is enabled correctly.


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