How to change Azure tunnel interface IP

netw0rk-newb · 2025-05-15T09:04:42.041Z

Hello,

Im trying to setup a BGP with my Azure cloud server from my firewall Sophos.
There are 2 IPSEC VPN (Route-based) between the two.
Since i have more than 1 routes for redundancy.
I am trying to use BGP instead of Static Route.

However since this is a RBVPN, my BGB in Sophos requires the tunnel peer IP of the Azure Cloud Server.
But two WAN connections in the Azure cloud have similar tunnel IP.
I was told they are created by default and im not sure to change them.
here is the config from Azure.

int tunnel 11
  ip address 169.254.0.1 255.255.255.252
  tunnel mode ipsec ipv4
  ip tcp adjust-mss 1350
  tunnel source 10.10.10.254
  tunnel destination 172.16.100.2
  tunnel protection ipsec profile Neo-OnPrem-VPN-Subisu-IPsecProfile
  exit

int tunnel 12
  ip address 169.254.0.2 255.255.255.252
  tunnel mode ipsec ipv4
  ip tcp adjust-mss 1350
  tunnel source 10.10.10.254
  tunnel destination 172.16.200.2
  tunnel protection ipsec profile Neo-OnPrem-VPN-Subisu-IPsecProfile
  exit

My Sophos VPN Tunnel IP
ISP1 : 169.254.0.1 255.255.255.252
ISP:2: 169.254.0.2 255.255.255.252

My plan for tunnel IT between Sophos to Azure
Sophos ISP1 Tunnel IP: 3.3.3.3
Azure Tunnel 1 IP: 3.3.3.4

Sophos ISP1 Tunnel IP: 4.4.4.3
Azure Tunnel 1 IP: 4.4.4.4

Im confused as which tunnel is being used as i see tunnel 11 and tunnel 12 on the config of azure.
Which tunnel should i use and is there a way to change them to my requirement?

popeyesailzzz · 2025-05-20T20:10:00.091Z

You need to drill down on the resource in azure and find out what the public ip interface object shows. You can disassociate the object, change it then bind it back to the virtual network gateway.

netw0rk-newb · 2025-05-28T03:32:57.548Z

that being said.
how do i change the both tunnel 1 n 2 ip address?

spiceuser-vxad · 2025-05-28T09:32:11.599Z

Thanks for the related information

popeyesailzzz · 2025-05-28T17:46:22.354Z

Is the sophos firewall in azure? The ips are assigned to the network interfaces in azure then attached to the firewall, set static ips. Use those static ips for tunnel interfaces.