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Hi,<br>
<br>
As promised I tell you about my experience with loadbalancing x2go.<br>
<br>
I had first tried to use the default loadbalancing setup of x2go
broker. It was working fine except that the Windows client was not
connecting to the https broker (due to a bug in the client). It has
been fixed quickly and I thank the development team for their
reactivity.<br>
<br>
In the meanwhile, I had looked up alternative solutions and here is
what I set up :<br>
<br>
The broker is a simple <a href="http://haproxy.1wt.eu/">HAProxy</a>
loadbalancer configured for ssh connections balancing. For us it
listens on port 10000 and dispatches ssh/tcp connections over 2 x2go
servers on ports 22 (the default ssh port !). The balancing
algorithm is based upon source ip hashing : It gives returning users
a chance to be sent to the same x2go server next time and have the
possibility to resume a suspended session (better than round-robin).<br>
<br>
Advantages of that solution :<br>
- x2go servers are not exposed to the outside world and there is no
need to open ports on the firewall for each x2go server : You only
need to open ports for the loadbalancer, which you can put in your
dmz.<br>
- HAProxy cares to dispatch connections only to x2go servers that
are up (timeout configuration).<br>
- Authentication is only made once on x2go servers (they are
configured with ldap_pam).<br>
- No need to install a session broker agent on x2go servers.<br>
<br>
Drawbacks :<br>
- When a user connects with a different public ip, he wont probably
be sent to the same x2go server where he could have a suspended
session.<br>
- Authentication is not made by the loadbalancer so there aren't acl
management as with the regular x2go broker.<br>
- Every connections transit through the loadbalancer so there might
be a little overhead. HAProxy is pretty optimized though and it is
not noticeable.<br>
<br>
I join hereby the HAProxy configuration file I am using.<br>
<br>
It really works fine for us. I hope it will be useful to others.<br>
<br>
Best regards,<br>
<br>
Thierry<br>
<br>
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