Zato quickstart on py3/centos is using mssql db?

Hi, I have installed zato on my Centos 7 according to the instructions for python3 and created the quickstart environment. It seems to start OK, but ping gives error “No server is available to handle the request”. Server logs are empty and there are no pidfiles.
When I start a server separately on forground, I get this:

`(base) [zato@localhost qs-1]$ zato start server1 --fg

2020-11-22 18:49:22,301 - WARNING - 11233:MainThread - zato.common.util.proc:113 - Stderr received from program /opt/zato/3.1.0/code/bin/py -m zato.server.main /opt/zato/env/qs-1/server1 fg=TrueZATO_ZATO_ZATOsync_internal=FalseZATO_ZATO_ZATOsecret_key=ZATO_ZATO_ZATOstderr_path=None 2> /tmp/tmpdjg2cs4t-zato-start-server.txt e:Traceback (most recent call last): File "/opt/rh/rh-python36/root/usr/lib64/python3.6/", line 193, in _run_module_as_main "__main__", mod_spec) File "/opt/rh/rh-python36/root/usr/lib64/python3.6/", line 85, in _run_code exec(code, run_globals) File "/opt/zato/3.1.0/code/zato-server/src/zato/server/", line 60, in <module> from zato.common.odb.api import ODBManager, PoolStore File "/opt/zato/3.1.0/code/zato-common/src/zato/common/odb/", line 37, in <module> from zato.common.mssql_direct import MSSQLDirectAPI, SimpleSession File "/opt/zato/3.1.0/code/zato-common/src/zato/common/", line 16, in <module> import pytds ModuleNotFoundError: No module named 'pytds'
It seems the quickstart environment is using MSSQL for ODB, on Centos(!).
But installing python-tds does not help.

Is there something wrong with my environment?
Is there a way to create the quickstart environment with some other database?
Or should I take a slow-start approach?

Hello @esa,

Zato does not use MS SQL under CentOS nor anywhere else by default.

Can you please send output from the command below?

$ zato --version

Good morning,

I’m using the latest version, I suppose: Zato 3.1+rev.ca1ade1bd-py3.6.9

Yes, I checked the configuration of my qs env and verified that it is supposed to use sqlite and it does, too:
$ file zato.db
zato.db: SQLite 3.x database

Zato does not use MSSQL but the server loads the driver. And fails to import pytds.
I guess the problem is just that python-tds is missing from requirements.txt.

I installed python-tds with pip, but it had no effect. I could see that it was installed, but pip list looked surprisingly empty compared to requirements.txt. It turned out that zato user was running miniconda, but just for starting the server that runs under another environment.

I made a temporary fix by copying pytds and python_tds-1.10.0 from /opt/zato/miniconda3/lib/python3.6/site-packages to /opt/zato/current/lib64/python3.6/site-packages. Problem solved!


yes, this is the latest version - any time you are unsure, you can just install the latest updates per the instructions here.

As to Miniconda, Zato does not use it for any purposes.

About the rest - from now on, I ask you to provide the exact commands that you run along with the exact output that you receive instead of a description of what was done.

Thank you.