🐛 BUG: Stoping Nebula does not free up port :4242
azukaar opened this issue · comments
What version of nebula are you using?
1.7.12
What operating system are you using?
all
Describe the Bug
When running Nebula programmatically, it does not free up port :4242
This is causing some issues, for example re-connecting on the Android app requires restarting the app completely to bypass the error complaining about the port being already busy.
You can test this easily like this:
package main
import (
"github.com/slackhq/nebula"
"github.com/slackhq/nebula/config"
"github.com/sirupsen/logrus"
"os"
"fmt"
"time"
)
func startNebula(configRaw []byte) *nebula.Control {
logrus := logrus.New()
logrus.Out = os.Stdout
logrus.Info("## Starting nebula")
c := config.NewC(logrus)
err := c.LoadString(string(configRaw))
if err != nil {
fmt.Println(err)
return nil
}
// Adjust PKI paths to be absolute
l, err := nebula.Main(c, false, "", logrus, nil)
if err != nil {
fmt.Println(err)
return nil
}
l.Start()
logrus.Info("## Started Nebula")
return l
}
func main() {
// read config from test.yml
config, err := os.ReadFile("test.yml")
if err != nil {
fmt.Printf("Failed to read config: %v", err)
return
}
l := startNebula(config)
time.Sleep(2 * time.Second)
l.Stop()
time.Sleep(2 * time.Second)
startNebula(config)
}Logs from affected hosts
No response
Config files from affected hosts
No response
Hi @azukaar -
AFAIK, calling nebula.Main multiple times is unsupported and listen.port is not a reloadable setting. In other words, this is expected behavior. Maybe you can describe more clearly what you're trying to achieve?
This is causing some issues, for example re-connecting on the Android app requires restarting the app completely to bypass the error complaining about the port being already busy.
If you're experiencing a bug with Mobile Nebula, please file a ticket at https://github.com/DefinedNet/mobile_nebula. This isn't something I've seen reports of, nor do I experience myself. In the mobile app, IIRC, we kill the Nebula process and create a new one when restarting. Although we also tend to use an ephemeral port...
I was writing a OS service was a desktop application connecting to Nebula
Having to restart the service on every disconnection is a little overkill in what you would normally expect to be doing (just stop() and start() the service)
Feel free to close the ticket if that's not something you plan on improving
Hi @azukaar -
Nebula was written as an application first and so the code was written in such a way that it expects a systemctl stop nebula (for example), shutting the entire process down and bringing it back up.
Some initial support for using Nebula like a library was first added in order to support Mobile Nebula, IIRC.
Some configuration can be reloaded via the reload() call. Does this achieve what you're looking for? Another option might be to run Nebula in a disposable sub-process.
Thanks for your input!
I will just restart the service for now (reload() does not work as I would like to possibly change the config)
@azukaar I think that's the best option at the moment...
But I didn't mean to imply this isn't something we would like to support. Just not something we seem to have tackled yet.
Can you share which platform you're running on?
Yes I saw this code that is why I was confused and marked it as a bug,
if you try the code I sent earlier you will see that the port is indeed not closed (tested on both Android and Windows with 1.7.2)
I closed the ticket after your previous comment but if you agree it is actually a bug it can be re-opened
@azukaar Were you able to re-test with master?
Sorry for delay @johnmaguire the issue cannot be reproduced on @master branch
No worries, thanks for checking. Closing as fixed by a3e59a3