GRE Tunnel speed very slow

Question

I have a remote VPS with Vultr that announces my /24 IP block.

Currently, I've got a GRE tunnel set-up between that VPS and a VM at my home that sends the traffic of a small IPv4 block over it. However, I only get download speeds of between 5 to 10 mbit/s. My home internet and the Vultr VPS and capable of much more than that.

These are the commands I use with Vultr:

modprobe ip_gre
ip tunnel add gre1 mode gre remote 94.x.x.x local 45.x.x.1
ip link set gre1 up
ip addr add 10.245.0.1/30 dev gre1
ip route add 45.x.x.16/28 dev gre1

And these are the commands for the VM at home:

modprobe ip_gre
ip tunnel add gre1 mode gre remote 45.x.x.1 local 192.168.254.178
ip link set gre1 up
ip addr add 10.245.0.2/30 dev gre1
ifconfig ens192 up
ip addr add 45.x.x.17/28 dev ens192

The tunnel is working, but it's very slow. Like I said, only 5-10 mbit/s which is not what I expect, as speedtests show, the Vultr VPS can do between 1-2 gigabit and my home connection can do between 400-500 megabit.

I have no clue what could be causing it to be this slow. Any ideas on why it is so slow?

Answer 1

The issue above was due to a firmware issue with the modems from my ISP. The workaround is to use Foo over UDP with GRE in it.

Answer 2

Use ipip tunnel i think youre using ziggo in netherlands. I have the same config but instead of gre i use ipip on ziggo line and its full speed.

The connect boz from ziggo has bad firmware with gre tunneling