Update Jenkins failed to connect afterward - jenkins

Question

I'm having a nightmare trying to update our Jenkins server. We are using a Debian VM to host our server. Last time it was updated was 2 years ago. So I have cloned the VM in case of trouble (thank god cause there is). I downloaded the newest war file and moved it to /usr/share/jenkins and done:
service jenkins stop
service jenkins start
I'm updating from 2.190.3 with java 8 still installed.
From there, I tried to go on my browser to check the update was done and end-up with a 502 bad gateway page.
When I try:
java -jar jenkins-cli.jar -s http://localhost:8080/ version
I get:
java.net.ConnectException: Connection refused (Connection refused)
at java.net.PlainSocketImpl.socketConnect(Native Method)
at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350)
at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206)
at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
at java.net.Socket.connect(Socket.java:607)
at java.net.Socket.connect(Socket.java:556)
at sun.net.NetworkClient.doConnect(NetworkClient.java:180)
at sun.net.www.http.HttpClient.openServer(HttpClient.java:463)
at sun.net.www.http.HttpClient.openServer(HttpClient.java:558)
at sun.net.www.http.HttpClient.<init>(HttpClient.java:242)
at sun.net.www.http.HttpClient.New(HttpClient.java:339)
at sun.net.www.http.HttpClient.New(HttpClient.java:357)
at sun.net.www.protocol.http.HttpURLConnection.getNewHttpClient(HttpURLConnection.java:1226)
at sun.net.www.protocol.http.HttpURLConnection.plainConnect0(HttpURLConnection.java:1162)
at sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:1056)
at sun.net.www.protocol.http.HttpURLConnection.connect(HttpURLConnection.java:990)
at sun.net.www.protocol.http.HttpURLConnection.getOutputStream0(HttpURLConnection.java:1340)
at sun.net.www.protocol.http.HttpURLConnection.getOutputStream(HttpURLConnection.java:1315)
at hudson.cli.FullDuplexHttpStream.<init>(FullDuplexHttpStream.java:71)
at hudson.cli.CLI.plainHttpConnection(CLI.java:279)
at hudson.cli.CLI._main(CLI.java:271)
at hudson.cli.CLI.main(CLI.java:83)
But when I check status of Jenkins:
● jenkins.service - LSB: Start Jenkins at boot time
Loaded: loaded (/etc/init.d/jenkins; generated; vendor preset: enabled)
Active: active (exited) since Sat 2021-06-26 12:26:17 BST; 1min 9s ago
Docs: man:systemd-sysv-generator(8)
Process: 2269 ExecStop=/etc/init.d/jenkins stop (code=exited, status=0/SUCCESS)
Process: 2308 ExecStart=/etc/init.d/jenkins start (code=exited, status=0/SUCCESS)
So I am a bit confused. Any ideas?

Answer 1

Following these steps instead of downloading the war file and moving it.