(SOLVED) Help connecting to local zerotier from docker ztnet - APIError

[ov-n]

Hi all,

I have a zerotier central-administered network. I would like to host my own controller. I have set up an Oracle VM with ubuntu, installed non-docker zerotier and everything works fine, the VM is in the zerotier network now.

I have then installed ZTNET using docker - my first time using docker and I read that docker is best way to go etc.

Install went fine. The I used the Migration Guide to connect to the local zerotier installation. I have commented out all that was necessary: services, volumes ,depends on; created the file local.conf in var/lib/zerotier-one with the required content - allowing management from 0.0.0.0/0, restarted zerotier-one service.

After opening port 3000 in the Oracle VPS and the VM I can access the controller at my VM IP and port 3000.

I went to ZT Controller area. I have put in the IP address of my VM and port 3000.

I have no local networks defined, the only one is in Zerotier Central. So I did nto expect any 'unlinked' networks to show up.

However, before anything else, I have this error popping up that is threatening to leave me bald:

A red notification: Error: APIError: An error occurred fetching data from http://address:9993/controller/network (get_controller_networks).

In the Local Controller area I get "No Networks have been created yet. Start by creating one..." etc. I guess this was expected.

However, when i click on Create a Network, after a while, I get the message: "Could not create network! Please try again"

Of course I tried again, many times. Same result.

I have tried to find similar problems from others but could not find much except to put in the zerotier key , which i did, in the ZT Controller section, from /var/lib/authtoken.secret. This really seemed a possible solution however, it made no difference. Same error messages.

I have managed to connect to the ZeroTier Central network by using a token I have generated in ZeroTier Central. However this will not help me much as this is just a way to manage the Central interface, not to bypass their restrictions.

I am hoping to get some ideas on what else to try to resolve this situation. I am considering uninstalling ZTNet docker version and docker and trying to install the 'normal' version.

(I am also looking to try to install ZTNet on my Raspberry Pi, however that is after / if I successfully resolve this of course).

Many Thanks!

PS I have also opened UDP port 9993 in Oracle VPS and in the local VM, still to no avail. I am out of ideas...

[ov-n]

Oh wow....

So I kept reading that I need UDP port 9996. But some posts (not many) suggested that i also need TCP port 9996.

So, as i had nothing else to do anymore, I went and opened TCP as well on 9996 and... it works!

Perhaps this TCP 9993 should be mentioned in the guide(s), together with the necessity for the auth token taken from the zerotier directory...

Anyway, happy I solved it. Now, on to checking if ZTNet can do routing (that is crucial to me) and how to install this on my RPi as well (backup in case Oracle decides to take the VM away from me).

👍🏻

[sinamics]

Thanks for sharing.
When running ZTNet in Docker while using a local (non-containerized) ZeroTier instance, the Docker network is isolated from the host. You need to open TCP port 9993 to allow ZTNet to communicate with the ZeroTier API.

I will update the docs.

[ov-n]

Can you please put this in the Migration tutorial? Also perhaps the need for the key contained from the zerotier locally installed package. I did not find these there, as far as I remember Many thanks Ovidiu From: Bernt Christian Egeland ***@***.***> Sent: Monday, 15 December 2025 9:49 PM To: sinamics/ztnet ***@***.***> Cc: ov-n ***@***.***>; Author ***@***.***> Subject: Re: [sinamics/ztnet] (SOLVED) Help connecting to local zerotier from docker ztnet - APIError (Discussion #805) Thanks for sharing. When running ZTNet in Docker while using a local (non-containerized) ZeroTier instance, the Docker network is isolated from the host. You need to open TCP port 9993 to allow ZTNet to communicate with the ZeroTier API. I will update the docs. — Reply to this email directly, view it on GitHub <#805 (reply in thread)> , or unsubscribe <https://github.com/notifications/unsubscribe-auth/B3QSVK42DMWLIB6ACEOI6PD4B2N4JAVCNFSM6AAAAACPALXTCOVHI2DSMVQWIX3LMV43URDJONRXK43TNFXW4Q3PNVWWK3TUHMYTKMRVHA4TCMI> . You are receiving this because you authored the thread. <https://github.com/notifications/beacon/B3QSVK2YWIHTLKP7YHYCIVT4B2N4JA5CNFSM6AAAAACPALXTCOWGG33NNVSW45C7OR4XAZNRIRUXGY3VONZWS33OINXW23LFNZ2KUY3PNVWWK3TUL5UWJTQA5DKR6.gif> Message ID: ***@***.*** ***@***.***> >