You’d think upgrading VMware would be transparent to the guest operating system. Not with vSphere 5.5: it broke my PPTP VPN. Here’s how I fixed it.
I run a Sophos UTM 9 firewall as a VM appliance on VMware 5.5. It works great, but to get PPTP VPN (which relies on GRE) working again after the upgrade, I had to change the VM’s settings and swap its network adapters from E1000 to VMXNET3.
1. Change the Guest Operating System Type
In the VM properties, change the guest operating system from “Other Linux”:
To “Red Hat Enterprise Linux 6”:
This lets you add virtual network adapters other than the E1000:
2. Remove the Existing NICs
3. Re-add the NICs as VMXNET3
When you’re done, the VM should look like this:
