Repeater Drops Server Connections Routinely?

[j.johnson]

I have the repeater setup and running as a service on a win 2008 server.

When trying to connect to computers through the repeater, we were running into hit and miss connections. Sometimes everything would connect fine, other times, it would not. Checking the server logs, they were showing the repeater service as crashing routinely (every 20-30 minutes). That would explain the issue...

So I uninstalled the service, removed the repeater, downloaded the new webgui version, re installed the service, disabled mode 1, and have watched the service for a few minutes.

The windows logs are no longer showing distributer.exe crashing, but while watching the repeater's webgui, it's showing the waiting servers slowly fill up with the computers that we have out there, then all of a sudden, all of them clear out, and slowly build up again. This cycle keeps repeating, maybe every 10 minutes. After the servers clear out, it seems to take around 3-4 minutes for most to re-appear, some however are on a longer cycle, and only re-appear one ever 2-3 times the list clears, which will still cause the same hit/miss issue of being able to connect.

The log also clears itself when the servers clear out. I can't find anything pointing to why this is happening, any advice?

[j.johnson]

Just tried to repeater that is bundled with ChunkVNC, it fails in the windows logs as well. went back to the webgui version again, atleast with this one I can see which servers are registered at any given time to know if the connection will succeed or not.

[Rudi De Vos]

There is indeed a cleanup that's done. It close idle (300sec) connections.
The problem is that we can not detect if the server is still online without sending data, but sending data would break the rfb protocol.

I will make an update with cleanup set to 3600 sec ( 1h), then we still get rid of the ghost connections and don't need to buildup the tree
every 5-10 minutes.

[urbanorox]

Im having the same issue, cant have more than 200 hosts connected to my repeater.

There is a ETA to the fix, if we can call this way, Mr Rudi?

[Rudi De Vos]

This can not be solved without changing the protocol.
Yes it can be fixed "easy" but then to old winvnc wil not longer work with the repeater and the old repeater wil not work with the new vnc.
Having a mix of different server/viewer versions this is a hell...some control mechanism is needed and that's hard as you can't change the
way how old servers behave.
No eta have been set.

[urbanorox]

Thanks for the fast answer! Ok, got about the ETA.

When time comes and large scale tests become needed, let me know, sir!

[Rudi De Vos]

Some test

added keepalive to repeater server/connection part
added keepalive to vnc server

Old server fail to connect to repeater and breaks connection
new server also works with old repeater
Keepalive is every minute
Time server connection is updated every minute ( visable in gui) , this avoid the disconnect in the cleanup code.

Download ( rep + vnc server )
http://www.uvnc.eu/download/repeater/ne ... r_test.zip

Please test if this is better.
viewer part isn't changed, so viewers still get disconnected, this makes it easier to explain.
all viewers work, only new server is required for new repeater.

[urbanorox]

I will test tomorrow and report what we got.

Thanks in advance!

[urbanorox]

I could run some tests just now and see what we have:

Old server fail to connect to repeater and breaks connection
Check, same thing happened here

new server also works with old repeater
not tried yet

Keepalive is every minute
Time server connection is updated every minute ( visable in gui) , this avoid the disconnect in the cleanup code.
I see the trick, it works just as intended, really nice

viewer part isn't changed, so viewers still get disconnected, this makes it easier to explain.
all viewers work(OK), only new server is required for new repeater.[this wasn't a rule in my tests. Some, not all, but a few old servers worked fine with the new repeater]


I will extend these tests tomorrow and report again in a bigger scale.

Thank you.

[Rudi De Vos]

The keepalive is send after 1 minute, i think a debug beep is still in the code. ( each 60 sec repeater beep)

Take care, results could be influenced by
An old server stay connected until keepalive is send, then he don't understand the message and close the repeater connection.
If old server is connected to viewer in this interval 1-60, then the repeater works like before as the keepalive is never sended.

[urbanorox]

Hi,

The new repeater now works as it should, without clean my host list.
But sometimes, some servers dont connect to the repeater. A simple service restart dont work anymore, but i think it has nothing to deal with this forum topic.

I'll keep testing. Thank you Rudi.