Keep a dotnet run command going after disconnecting from SSH? - .net-core

I am trying to keep a dotnet run command going after terminating the SSH session I started the command on.
I am trying to use nohup, although it doesn't seem to work as advertised:
nohup dotnet run --project=CBU &
It seems to print out the following, but still block input to the CLI:
nohup: ignoring input and appending output to 'nohup.out'
Terminating the SSH session shows that the application stops executing.

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How to use Robot framework to write Get adb log after Enter Ctrl+c to automatically execute the function in Terminal and Windows CMD?

How to use Robot framework to write Record 15 secs Android adb log after enter Ctrl+c to automatically execute the function in Terminal and Windows CMD??
adb shell logcat -b crash > log_carsh_date.txt
Record 15 secs
Enter Ctrl+c
Can you help me? Thank you.
${result} = Run adb shell logcat -b crash > log_carsh_date202221027.txt
Sleep 15s
AutoItLibrary.Send {^c}
Instead of using OperatingSystem.Run you most probably would be better served by using Run Process keyword from Process Library. You can see there the arguments for capturing the output directly and setting a timeout.
I have never used logcat but the command would probably look something like this
${result}= Run Process adb shell logcat -b crash > log_carsh_date202221027.txt timeout=15s
The ${result} is a result object, which you can get different properties out of after the run as explained in the documentation.

CLI dotnet run with another command

I need to run the command line dotnet run, after starting the url localhost, I need to run another command like curl.
I could do like it:
dotnet run & sleep 12; curl http://localhost:59406
but if dotnet run delay more then 12 seconds, it will be stopped.
It may be possible to solve with linux commands, but I am not experienced in this.
If that helps, I will use this when building the Azure DevOps pipeline, to run newman tests on localhost
You can extend the sleep time if dotnet run takes longer to start up your application, to make sure your application is started when curl the url localhost
If you use this in azure devops pipeline, you can use two bash tasks to run above command. The first bash task run dotnet run & to start your application in the background. The second bash task run curl to curl url localhost. See below yaml pipeline example.
- bash: |
#cd ConnectionWeb/ConnectionWeb
#dotnet restore
dotnet run &
- bash: |
curl http://localhost:8881

paramiko and nohup ''

OK so I have paramiko v2.2.1 and I am trying to login to a machine and restart a service. Inside the service scripts it basically starts a process via nohup. However if I allow paramiko to disconnect as soon as it is done the process started terminates with a PIPE signal when it writes to stdout.
If I start the service by ssh'ing into the box and manually starting it there is no issue and it runs in the background fine. Also if I add long sleep 10 before disconnecting (close) paramiko it also seems to work just fine.
The service is started via a init.d script via a line like this:
env LD_LIBRARY_PATH=$bin_path nohup $bin_path/ServerLoop.sh \
"$bin_path/Service service args" "$#" &
Where ServerLoop.sh simply calls the service forever in a loop like this so it will never die:
SERVER=$1
shift
ARGS=$#
logger $ARGS
while [ 1 ]; do
$SERVER $ARGS
logger "$SERVER terminated with exit code: $STATUS. Server has been restarted"
sleep 1
done
I have noticed when I start the service by ssh'ing into the box I get a nohup.out file written to the root. However when I run through paramiko I get no nohup.out written anywhere on the system ... ie this after I manually ssh into the box and start the service:
root#ts4700:/mnt/mc.fw/bin# find / -name "nohup*"
/usr/bin/nohup
/usr/share/man/man1/nohup.1.gz
/nohup.out
And this is after I run through paramiko:
root#ts4700:/mnt/mc.fw/bin# find / -name "nohup*"
/usr/bin/nohup
/usr/share/man/man1/nohup.1.gz
As I understand it nohup will only redirect the output to nohup.out if "If standard output is a terminal" (from the manual), otherwise it thinks it is saving the output to a file so it does not redirect. Hence I tried the following:
In [43]: import paramiko
In [44]: paramiko.__version__
Out[44]: '2.2.1'
In [45]: ssh = paramiko.SSHClient()
In [46]: ssh.set_missing_host_key_policy(AutoAddPolicy())
In [47]: ssh.connect(ip, username='root', password=not_for_so_sorry, look_for_keys=False, allow_agent=False)
In [48]: stdin, stdout, stderr = ssh.exec_command("tty")
In [49]: stdout.read()
Out[49]: 'not a tty\n'
So I am thinking that nohup is not redirecting to nohup.out when I run it through paramiko because tty is not returning a terminal. I don't know why adding a sleep(10) would fix this though as the service if run on the command line is quite verbose.
I have also noticed that if the service is started from a manual ssh its tty in the ps ax output is still set to the ssh tty ... however if the process is started by paramiko its tty in the ps ax output is set to "?" .. since both processes are run through nohup I would have expected this to be the same.
If the problem is that nohup is indeed not redirecting the output to nohup.out because of the tty is there a way to force this to happen or a better way to run this sort of command via paramiko?
Thanks all, any help with this would be great :)

nohup - dont want nohup.out but want log going to a different file on the remote server

I'm running the following command (where variables have valid values for ssh command and $file - is a .sql file).
nohup ssh -qn ${ssh_user}#${dbs} "sqlplus $dbuser/${dbpswd}#${dbname} <<ENDSQL | tee "${sql_run_output_file}".ssh.log
set echo off
set echo on
set timing on
set time on
set serveroutput on size 1000000
#${file}
ENDSQL
"
When I was using the above command without "nohup" before ssh command, after 1 hour or so, my connection from source server (where im running ssh) was getting an error/message "Connection reset...." and hanging my BASH shell script (which contains this ssh command in it). When, I use nohup, i dont see the connection issue.
Here's what I'm trying to get and need your help.
Change the command shown above so that the command will NOT create a nohup.out
(Did I read that I can use > instead of | tee ... and use 2>&1)
I DO NOT want to run the command giving a "&" (background)
I DO want a LOG file for the sqlplus session that's running on the target DB server via ssh command/connection (initiated from source server).
Thanks.
You can still lose the connection when running ssh under nohup, so it's not really a good solution. If possible, I would recommend that you copy the sql file via scp to the target server, then ssh in to the server, open a screen and run the command from there (Or run it under nohup). Is that an option?

Jenkins seems to be the target for nohup in a script started via ssh, how can I prevent that?

I am trying to create a Jenkins job that restarts a program that runs all the time on one of our servers.
I specify the following as the command to run:
cd /usr/local/tool && ./tool stop && ./tool start
The script 'tool' contains a line like:
nohup java NameOfClass &
The output of that ends up in my build console instead of in nohup.out, so the job never terminates unless I terminate it manually, which terminates the program.
How can I cause nohup to behave the same way it does from a terminal?
If I understood the question correctly, Jenkins is killing all processes at the end of the build and you would like some process to be left running after the build has finished.
You should read https://wiki.jenkins-ci.org/display/JENKINS/ProcessTreeKiller
Essentially, Jenkins searches for processes with some secret value in BUILD_ID environment variable. Just override it for the processes you want to be left alone.
In the new Pipeline jobs, setting BUILD_ID no longer prevents Jenkins from killing your processes once the job finishes. Instead, you need to set JENKINS_NODE_COOKIE:
sh 'JENKINS_NODE_COOKIE=dontKillMe nohup java NameOfClass &'
See the wiki on ProcessTreeKiller and this comment in the Jenkins Jira for more information.
Try adding the & in the Jenkins build step and redirecting the output using > nohup.out.
I had a similar problem with runnning a shell script from jenkins as a background process. I fixed it by using the below command:
BUILD_ID=dontKillMe nohup ./start-fitnesse.sh &
In your case,
BUILD_ID=dontKillMe nohup java NameOfClass &

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