Troubleshooting

By Lex Li

This page shows you how to troubleshoot common issues.

How to troubleshoot client/server connectivity?

Answer: First please follow server component installation steps to review if you have executed every steps.

Second, check the issues step by step,

Certificate

Assume that we register the certificate to port 8088. Run the following command,

sudo httpcfg -list

You must see the port and certificate thumbprint listed which is similar to below,

Port: 8088 Thumbprint: 38A913B07B138730DC9B7B13DC4F51310ADC6C93

Otherwise, the certificate was not properly registered.

Service Address

Assume that we are using a machine whose IP address if 192.168.18.129. Run the following command,

ifconfig

You can see the “inet address” for each network adapters, and learn which are the valid IP addresses you can use in service address.

Note

netstat can be used to make sure the remote services instance is monitoring the service address.

For example, if the remote services instance is launched by the following command,

mono RemoteServicesHost.exe https://0.0.0.0:8088

then run netstat should show that TCP port 8088 is being listened at,

netstat -an | grep "LISTEN "
tcp     0     0 0.0.0.0:8088      0.0.0.0:*       LISTEN

The port number used in service address must have a server certificate registered. Otherwise, the client cannot make an HTTPS connection to the server side.

Firewall

Linux distributions normally come with built-in firewall products. So exceptions for the port chosen for Jexus Manager server component must be made. You have to refer to the corresponding distro or firewall manuals to learn how to create such firewall exceptions. If you choose port 8088, then TCP access to that port must be registered as an exception.

If the client/server connection goes through the Internet, you should be even more caution that sometimes the connection can be blocked unexpectedly. Try to use another port number (such as 12345) and try again.

Note

On Ubuntu the following command can be used if you use the default firewall,

sudo ufw allow 8088

REST Test

The service address (such as https://192.168.18.129:8088) and user credentials (jexus|lextudio.com) can be used to test out the server component availability via curl or WFetch.

Note

The curl command can be

curl --header "X-HTTP-Authorization: jexus|lextudio.com" -k https://192.168.18.129:8088/api/server

The server should reply with 200 if configuration is correct.

What if client side reports connection failure and the error message is not clear enough?

Answer: JexusManager.exe writes the exception details to a file named “debug”. Open it and you will see the information.

For Jexus Manager 2.0 and above, this debug log file is located at My Documents\Jexus Manager\temp\debug.

What is the cause of “System.Reflection.TargetInvocationException” when starting/stopping Jexus Manager Remote Services?

Answer: If the exception details match below, then please make sure you pass a valid service address to RemoteServicesHost.exe.

Unhandled Exception:
System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.Net.Sockets.SocketException: The requested address is not valid in this context
  at System.Net.Sockets.Socket.Bind (System.Net.EndPoint local_end) [0x00000] in <filename unknown>:0
  at System.Net.EndPointListener..ctor (System.Net.IPAddress addr, Int32 port, Boolean secure) [0x00000] in <filename unknown>:0
  at System.Net.EndPointManager.GetEPListener (System.String host, Int32 port, System.Net.HttpListener listener, Boolean secure) [0x00000] in <filename unknown>:0
  at System.Net.EndPointManager.AddPrefixInternal (System.String p, System.Net.HttpListener listener) [0x00000] in <filename unknown>:0
  at System.Net.EndPointManager.AddListener (System.Net.HttpListener listener) [0x00000] in <filename unknown>:0