NS8 How to restart an instance

LayLow · November 14, 2023, 1:33pm

Hi,

How can one restart an instance form the admin web interface please? Any instance of any application for that matter (restart a container??).

Thanks!

davidep · November 14, 2023, 2:33pm

Neither applications nor the whole node can be restarted from the cluster-admin UI.

capote · November 14, 2023, 3:46pm

Isn‘t it a valid requirement?

davidep · November 14, 2023, 5:20pm

So let’s talk about a new feature!

Why do I want to restart a NS8 node? Usually after a kernel update.

How we can restart a NS8 node? So far we have the following options:

Log in by SSH or on the system console and run the reboot or systemctl reboot commands
For bare metal, press the power button
For cloud VPS, use the provider web UI or APIs
For local virtual environment, use the virtual “power button”

davidep · November 14, 2023, 5:32pm

but you’re asking for an application instance… Sorry I didn’t get it.

Why do you want to restart an application? What is the issue?

LayLow · November 14, 2023, 6:50pm

Not a specific issue, rather be in control. I would like to be able to start, stop instances/containers for whatever reason. Many use cases come to mind, but it all basically boils down to be in control.

Thanks

davidep · November 14, 2023, 8:07pm

I’d rather consider to switch off/on a complete application in that case.

LayLow · November 14, 2023, 9:04pm

Yes indeed, that is what I meant. By completely switching off you mean spinning down all related containers to that specific application, and by switching back on you basically achieved a ‘reboot’ of that application?

davidep · November 14, 2023, 9:19pm

Exactly. Gaining too much control over individual parts might be counterproductive

LayLow · November 14, 2023, 9:29pm

Morphing into feature request.

davidep · November 20, 2023, 8:34am

Filed here NethServer 8 · GitHub

peter1 · March 13, 2024, 9:21pm

It sounds like this isn’t a priority, and I am afraid to ask because how the development team is acting. But I will ask anyway I feel it is important. How do I turn on/off an application instance from the command line?

stephdl · March 13, 2024, 9:31pm

runagent -m webserver1

systemctl disable --user --now webserver.service

pike · March 16, 2024, 12:30pm

It’s gonna be a joy when dependecies will happen that I reboot a module, than all other dependand modules will be rebooted correctly as dependancy need…
Like services. Of an operating system. Not linux…

stephdl · March 16, 2024, 12:51pm

An event system exist to publish the changes on a module like for mail or LDAP and ask to restart other modules that are registered to this event. For example roundcubemail listen the event mail-settings-changed event to know if it needs to restart to auto discover where is the mail server or any other settings it needs from the mail server

But the main difference before the good old time of NS7 is that IF a module needs a database or other app, they are included inside the pod, for example webserver is the pod, if you restart it you restart nginx and phpfpm

No more services linked to other services like before, everything is inside the pod that you could consider like a mini standalone server itself

github.com

NethServer/ns8-mail/blob/main/imageroot/actions/configure-module/90publish_srv_keys#L47


      
          trx.delete(ksubmission).hset(ksubmission, mapping={
              "port": "10587",
              "host": node_address,
              "node": str(node_id),
              "user_domain": udomname,
              "module_uuid": module_uuid,
              "mail_hostname": hostname
          })
          
          # Publish change event
          trx.publish(agent_id + "/event/mail-settings-changed", json.dumps({
              "reason": os.getenv("AGENT_TASK_ACTION", "unknown"),
              "module_id": os.environ['MODULE_ID'],
              "node_id": node_id,
              "module_uuid": module_uuid,
          }))
          
          trx.execute()

github.com

NethServer/ns8-roundcubemail/blob/main/imageroot/events/mail-settings-changed/80start_services#L15


      
          # SPDX-License-Identifier: GPL-3.0-or-later
          #
          
          import json
          import sys
          import agent
          import os
          
          event = json.load(sys.stdin)
          
          if event['module_uuid'] == os.getenv('MAIL_SERVER', ''):
             # Restart to apply changed settings
             agent.run_helper("systemctl", "--user", "try-restart", "roundcubemail-app.service").check_returncode()

pike · March 16, 2024, 5:51pm

Yeah. Sure. Userbase, AD or LDAP flavour.

Andy_Wismer · March 16, 2024, 7:32pm

No difference to NS7…