CODEWITHSUNDEEP
routesgcloud
konradk
konradk

Reputation: 193

Gcloud VM additional network interface - no internet access

I'm trying to set up a VM with 2 interfaces. The first interface works fine, but the second not really.

gcloud compute instances create worker-0 \
--boot-disk-size 200GB \
--can-ip-forward \
--image-family ubuntu-2004-lts \
--image-project ubuntu-os-cloud \
--machine-type e2-standard-4 \
--metadata-from-file=startup-script=vm-startup-script.sh \
--network-interface network=$NET_INTERNAL,subnet=$SUBNET_INTERNAL,private-network-ip=192.168.10.3 \
--network-interface network=$NET_DN,subnet=$SUBNET_DN,private-network-ip=192.168.11.100 \
--scopes compute-rw,storage-ro,service-management,service-control,logging-write,monitoring \
--tags $NAME,worker

After that I'm testing it with ping

ping -I ens5 1.1.1.1 but it results in Destination Host Unreachable

I've read that for any additional interface we have to setup routing.

Following section https://cloud.google.com/vpc/docs/create-use-multiple-interfaces#configuring_policy_routing I've checked gateway using gcloud API - it is 192.168.11.1

So then I try

echo "1 rt1" | sudo tee -a /etc/iproute2/rt_tables
sudo ip route add 192.168.11.1 src 192.168.11.100 dev ens5 table rt1
sudo ip route add default via 192.168.11.1 dev ens5 table rt1
sudo ip rule add from 192.168.11.100/24 table rt1
sudo ip rule add to 192.168.11.100/24 table rt1


ip route
default via 192.168.10.1 dev ens4 proto dhcp src 192.168.10.3 metric 100 
172.17.0.0/16 dev docker0 proto kernel scope link src 172.17.0.1 linkdown 
192.168.10.0/24 via 192.168.10.1 dev ens4 proto dhcp src 192.168.10.3 metric 100 
192.168.10.1 dev ens4 proto dhcp scope link src 192.168.10.3 metric 100 
192.168.11.0/24 via 192.168.11.1 dev ens5 
192.168.11.1 dev ens5 scope link 
    
ip route show table 1
default via 192.168.11.1 dev ens5 
192.168.11.1 dev ens5 scope link src 192.168.11.100

But I still can't reach internet when using ping.

Firewall rules for this interface's network are set to allow all.

Is there anything I'm missing?

Upvotes: 0

Views: 235

Answers (1)

konradk
konradk

Reputation: 193

It turned out that the internet is actually reachable, ping works but only this way

ping -I 192.168.11.100 1.1.1.1 -c 1

When using interface as argument it fails, how is it possible?

Upvotes: 1

Related Questions