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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
solusVM.
   >> 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
[root@Node]#
  
  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:



HN#


   # 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.



VE#


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

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
================================================================================================================

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