Send print request from app engine front-end app to the printer sitting on internal network?

[Mapperkids]

Hi

We are running a front-end app that built on standard app engine, when we try to send a print request using the raw TCP port like http://192.168.4.15:9100 from Gcloud app engine to the local printer, it is not working, if we do the same with my local development machine it works fine, my question is how can we get around it without set up cloud VPN? I tried change the modem/router to turn on the DMZ zone and port forwarding, it works from a development machine that connect to public internet and access it through like external IP: http://93.33.47.33:9100 then forward it to the local printer at http:192.168.4.15:9100.  But when try on the Gcloud, it blocked and need to be in https:// and then time out.

Can I use dynamic DNS service? or the best and secure way is set up VPN between Gcloud and the internal network? I heard Gcloud is very picky on use which hardware firewall box in order to make the VPN tunnel working.

Thanks for any suggestions.

[Aref Amiri (Cloud Platform Support)]

Hi,

You would need to use Cloud VPN as it securely connects your existing network to your Google Cloud Platform (GCP) network through an IPsec VPN connection. However, App Engine Standard won’t be able to connect directly to VPN and you can only set up Cloud VPN over VPC networks, which is designed to work with GAE Flex or GCE VM. Since you are using App Engine Standard, you’d need to forward the traffic to GCE VM which is possible only via external IP and the GCE VM would act as a proxy.