Able to ping external but unable to ping own network

Anyone came across such issue before?

I have two Linux VM each with their own IP address and sharing a virtual IP.

From the two VM:

• can ping external IP
• cannot ping IP within same subnet (even gateway)

From machine in same subnet

• can ping everything except the two VM and virtual IP
• cannot hit any open ports on the two VM

From external network

• can ping the two VM
• can access all open ports on the VM

Things I have done:

• check virtual adapter is correct
• net mask is correct
• no mac address collision
• disconnect one of the vm and ping the other (unable to)
• arp table on gateway has mac address of both vm and virtual IP