Cloned VM generate same IPv6 link local addresses as the original VM

Solution Verified - Updated -

Issue

If some VM is cloned, the MAC address of it's NIC is generated to be unique by the hypervisor,

but the link-local IPv6 address is the same for the clone VM as well as for the original VM.

Such address is then marked as dead-failed and another one is generated.

Original VM

ens192: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT group default qlen 1000

link/ether 00:50:56:be:bd:4b brd ff:ff:ff:ff:ff:ff promiscuity 0 addrgenmode none numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535 

 inet6 fe80::2985:3be0:6417:91b5/64 scope link noprefixroute valid_lft forever preferred_lft forever

Cloned VM #1

ens192: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT group default qlen 1000

link/ether 00:50:56:be:58:6b brd ff:ff:ff:ff:ff:ff promiscuity 0 addrgenmode none numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535 

inet6 fe80::2985:3be0:6417:91b5/64 scope link tentative noprefixroute dadfailed  valid_lft forever preferred_lft forever
inet6 fe80::230b:b09e:b641:4f62/64 scope link noprefixroute  valid_lft forever preferred_lft forever

Cloned VM #2

ens192: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT group default qlen 1000

link/ether 00:50:56:be:11:b8 brd ff:ff:ff:ff:ff:ff promiscuity 0 addrgenmode none numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535

inet6 fe80::2985:3be0:6417:91b5/64 scope link tentative noprefixroute dadfailed valid_lft forever preferred_lft forever
inet6 fe80::230b:b09e:b641:4f62/64 scope link tentative noprefixroute dadfailed valid_lft forever preferred_lft forever
inet6 fe80::1546:1c0e:cc7d:928d/64 scope link noprefixroute valid_lft forever preferred_lft forever

Clone VM #3

ens192: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT group default qlen 1000

link/ether 00:50:56:be:b4:b7 brd ff:ff:ff:ff:ff:ff promiscuity 0 addrgenmode none numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535

inet6 fe80::2985:3be0:6417:91b5/64 scope link tentative noprefixroute dadfailed valid_lft forever preferred_lft forever
inet6 fe80::230b:b09e:b641:4f62/64 scope link tentative noprefixroute dadfailed valid_lft forever preferred_lft forever
inet6 fe80::1546:1c0e:cc7d:928d/64 scope link tentative noprefixroute dadfailed  valid_lft forever preferred_lft forever

So as can be seen all the VMs are generating the same IPv6 link-local addresses rows.

The Clone VM #3 does not have any functional IPv6 link-local address.

Environment

rhel-7
vmware
kvm

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