Mgmt Interface question

1- when i deploy an Aws Instance with F5 LB, the Mgmt interface and the Self-ip interface are the same. But if i attach other network interfaces, the interface 1.0 ( mgmt + self-ip ) change to inutilizable state and are asigned only for mgmt. Also looking the interface via CLI ( list net interface ) this interface lost mac-address value, and others.

The default AWS instance is set up as a 1-NIC setup, with the Management interface routed through the tmm interface. If you add a second interface, then the system reverts back to the standard multi-NIC setup with a dedicated Management interface on one NIC and other interfaces assigned to tmm. We do not support 1-NIC Management configuration with multiple interfaces.

2- There is a way to use a self-ip in the same subnet/network than mgmt interface ?

No - tmm interfaces cannot share address space with the Management interface. There is no way to determine which routes to use for traffic in this situation, so it cannot be configured. If you use CIDR you may be able to isolate your Management IP address from the Self-IP in adjacent network ranges.