Adding Ethercalc as application add some wrong route to my UCS server

just after installing Ethercal all my vpn user have lost access to the server, because ethercalc add a route used by my VPN.
the route 172.16.0.0/24 is used by my VPN, but ethercal set this route to
172.16.0.0/24 dev br-174713c1388e proto kernel scope link src 172.16.0.1

How can I add an application without setting this route ?
thanks for your directions.

regards from Tahiti

I have tried to set a route using
univention-config-registry set interfaces/eth0/route/myvpn=“net 172.16.0.0 netmask 255.255.255.0 gw 10.0.1.254”
but it doesn’t works
Ethercalc after reinstallation do not works anymore AND my vpn users are out
I really need Ethercalc to use another network, any solution for this ?

Hi,

Ethercalc as a docker-based application needs some internal “transport network” to get connectivity to your LAN. By default, docker apps use 172.16.1.1/16 for these networks.

Pitty your VPN uses the same range. If you can not reconfigure your network try to define a different range for the docker networks by using a UCR variable:

ucr set appcenter/docker/compose/network="172.20.1.1/16"
[Edited, now using private network as suggestion, according to comment from @ahrnke ]
I am currently unsure if your need to restart just docker or full UCS server. Try first:
systemctl restart docker

After this your Ethercalc should use a different network range.

If not, uninstall the app and reinstall again.

Hope it helps!

/CV

Using 172.10.1.1/16 for the Docker network may work but isnt the best choice as this is outside the range defined in https://tools.ietf.org/html/rfc1918 and actually used by AT&T.
I guess that looking for another unused /16-network inside 172.16/12 is more appropriate but needs some investigation (like this https://www.lullabot.com/articles/fixing-docker-and-vpn-ip-address-conflicts).

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You’re right, your suggestion work. I have set the route to 172.31.1.0/16 so its within the RFC1918 and it have enought IP.

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