Enable promiscuous mode - x360Recover

Written By Tami Sutcliffe (Super Administrator)

Updated at March 25th, 2022

There are times where more than one VM is running on an appliance and they can not ping each other. 

When this happens, you will need to enable promiscuous mode.

To enable promiscuous mode, first open a terminal on the appliance and log in as root. If you do not have the root password, contact Support and they can send it to you.

After you log in as root,  run

netstat -i

and you should see that eth0 has a flag of BMRU.

Next, run

ip link set eth0 promisc on

Now, run the netstat -i again and your flag should now be BMPRU.

Flag details are as follows:

B flag is for broadcast
M flag is for multicast
P flag is for promisc mode
R is for running
U is for up

When the DR is over, run

ip link set eth0 promisc off

To turn off promiscuous mode:

This setting should not be permanent and a reboot will clear the flag. You should not have to do this on all appliances. This issue is from a limitation of the NIC and Switch.

To make it per, add:

ip link set eth0 promisc on  above the Xeit 0 line in rc.local


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