Cannot connect to master: 111

i am testing this software and i am not able to connect the client to the server.
my setup is:

  1. os - oracle linux 9.u4
  2. machines are virtualized in virtualbox and network is briged.
  3. installed the latest thinlinc software.
  4. no dns but i have configured hosts file.
  5. configured vsmagent.hconf and pointed out to the 1st vm as the master.
    no clues in the log.
    what is the correct steps for setting up 1 vsm server (no ha) and multiple agents ?
    do i need to configure same users and passwords on all the machines ?
    do i need to do something with ssh ?


Hi @udi.mosh,

Have you set agent_hostname correctly in vsmagent.hconf? This parameter should be set to an IP address or hostname of the agent, which is directly accessible by the client. It should be different for each agent in the cluster.

You can find the documentation on how to do this here:

Yes. Generally each machine in the cluster will use the same authentication source, for example LDAP or Active Directory.

As long as you have an SSH server running on each machine, you shouldn’t have to do anything special.

Hope this helps, let me know if you have any further questions.

Hi aaron,
Thank you. I think i did it correctly but i will try again 2 days from now and let you know.

בתאריך יום ו׳, 5 ביולי 2024, 02:53, מאת Aaron Sowry via ThinLinc Community Forum ‏<>:

hi @aaron ,
things are not working. i have configured vsmagent and read the documentation and there is still 111 error.

  1. i do not use central auth. for me it is every linux to itself. does that matter ? do i have to have central auth to solve 111 ?
  2. maybe i am missing something here with the cluster purpose, the cluster is for load balancing to exact linux boxs ? i was under the impression that the master will have all it agents under a list and when i connect to the master i am presented with all the available linux boxs to choose from.
  3. i do not see any informative logs to help me understand this 111.
  4. do i have to configure certificates to solve 111 problem ? i have done regular install on both linux machine and haven’t changed the certificates what so ever.

Hi @udi.mosh.

Could you please clarify the “111 error”, since it is nothing I recognise or familiar with. Where is this error originating from, and are you able to provide the log file or error messages associated with it (or at the very least, a screenshot)?

You don’t have to use a central authentication mechanism, no. You can configure the accounts on each agent server individually. This can be inefficient for larger systems, though.

Normally, the master will choose which agent to start the session on, based on load. So a user logging in may end up on any one of the agents.

However, it is possible to configure ThinLinc so that each user has a dedicated agent, by using the subcluster functionality. See Configuring ThinLinc Servers in a Cluster — The ThinLinc Administrator's Guide 4.16.0 build 3491 documentation. So if you had a cluster of 5 agents, you would essentially configure 5 subclusters, each with only one specific user being allowed access.

As above, I’m not familiar with the 111 error, so will need more info. But valid TLS certificates are not a requirement. ThinLinc ships with self-signed certificates which will work, although most browsers will raise a warning.

hello @aaron ,
i have uploaded the system status of the agent showing the problem.

this is the vsmagent config in the agent…

here you can see that the server is identifying both it’s own agent and the other agent

There are parts of the ThinLinc Web Administration that are only meant to be used on the Master server. I understand that the interface is confusing, and showing the ”Cannot connect to master: 111”-error doesn’t help. Hopefully, we can improve this in the future. I added a bug in our systems for this.

When using Web Administration on a ThinLinc Agent, the following menus are not relevant:

  • Status → Licenses
  • Status → Load
  • Status → Sessions
  • VSM → Subclusters
  • VSM → Master

The above menus are only relevant for the ThinLinc Master. I hope that clarifies the error.

Are you also having problems connecting using a ThinLinc client?

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thank you very much for the clarification.
i didn’t had problems with connecting to both servers using both web and thin. the only problem i had was due to decentralized user management. i saw the thinlinc client trying to connect to the agent server and the server so load balancing seemed to work.

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