cups->ipp->cups->ipp->cups possible?

[Sebastian Fuchs]

Hello,

I want to forward print jobs over a VPN connection. The setup looks like this:

app. server ---- our vpn gateway ---- customer's vpn gw ---- printer

There is no routing through the VPN, connections are only possible to the next hop.
CUPS versions are 1.3.11 on the app server and 1.3.10 on the vpn gateways.

Printing from the local vpn gateway to the remote printers works but printing from the app server doesn't.

app server:
pr1 ipp://local vpn gw/printers/pr1

local vpn gw:
pr1 ipp://remote vpn gw/printers/pr1

remote vpn gw:
pr1 socket://printer:9100

When printing from the app server I get "Print-Job client-error-not-authorized: The printer or class is not shared!" at the local vpn gateway. Authentication is turned off as far as possible with "allow all" and removing any "require". The printers are shared at every host.
It seems that the scheduler on the local gw doesn't even contact the remote gw and immediately returns the authorization error.

As a work-around I use socket printing from the app server and something like "socat <port> | lpr -P <printer>" on the local gw.

Should the approach described above work in principle and if not, are there any recommendations for a vpn proxy setup?

I found this thread http://linux.derkeiler.com/Mailing-Lists/SuSE/2008-07/msg00105.html at the opensuse list which describes the same problem. But the solution there appeared kind of automagically and it doesn't work for me.

TIA for any input, I really need some hints on what to look for before spending more weekends on this.

Best regards,

Sebastian Fuchs