There are several steps that may be helpful in isolating and troubleshooting this issue. Note that it may be worth connecting with your IT admin first to confirm if there are any network or security policies that may be restricting traffic to and from your MATLAB Web App Server.
Check Server Status
Before anything else, confirm that your server is still running.
- For the product version of MATLAB Web App Server, you can check this by running the webapps-status script.
- For both the product and development versions of MATLAB Web App Server, you can check this by opening the Services program (from the Windows Start menu) and checking if the MATLAB Web Apps (R20XXx) and MATLAB Web Apps Launcher (R20XXx) services are both running.
Confirm Server URL
Confirm that the URL you are using to access the webapps homepage is correct. This includes the header (HTTP vs. HTTPS), hostname, and port.
To check the correct URL for your server:
- For the product version of MATLAB Web App Server, the webapps-start command will output the correct URL.
- For the development version of MATLAB Web App Server, the Open Home Page button will open the correct URL in a browser.
- For both versions, the webapps_service_start.out log file will list the correct homepage URL.
Test Access from Alternate URLs
To help isolate the issue, try a few simple tests.
- From the machine hosting the server:
- Confirm if you can access the homepage URL from this machine.
- Try accessing the webapps homepage using localhost instead of the FQDN. For example, if your homepage URL is try accessing the webapps homepage using the following URL instead:http://hostname.mydomain.com:9988/webapps/homehttp://localhost:9988/webapps/home
- Based on these results:
- If the default URL does not work but the localhost URL does work, this may be an issue with DNS resolution -- contact your IT admin.
- If neither the default URL nor the localhost URL are accessible from the machine hosting the server, skip to the "Check Ports" section below.
- If connections work from the host machine but not from other clients, continue to the next bullet to troubleshoot connections from the client machine.
- From the client machine:
- Confirm if you can access the homepage URL from this machine.
- Try accessing the webapps homepage using the server's IP address instead of the FQDN. You can find the correct IP address by running the command ipconfig from a Windows command prompt on the server machine and looking for the IPv4 Address. For example, if your homepage URL is try accessing the webapps homepage using the following URL (with your IP address) instead:http://hostname.mydomain.com:9988/webapps/homehttp://172.12.345.67:9988/webapps/home
- Based on these results:
- If the default URL does not work but the IP address does work, this may be an issue with DNS resolution -- contact your IT admin.
- If neither URL works, continue to the steps below.
Check Connectivity
You can check connectivity between the client and server machines via ping. Note that Windows machines may have pings disabled by default -- check your firewall settings to confirm.
To run this test, open a command prompt on the client machine and run the ping command with either the server's hostname or IP address, e.g.:
ping hostname.mydomain.com
or
ping -a 172.12.345.67
If the client machine is able to successfully connect to the server machine, you should receive a response like:
Pinging hostname.mydomain.com [172.12.345.67] with 32 bytes of data:
Reply from 172.12.345.67: bytes=32 time<1ms TTL=125
Reply from 172.12.345.67: bytes=32 time<1ms TTL=125
Reply from 172.12.345.67: bytes=32 time<1ms TTL=125
Reply from 172.12.345.67: bytes=32 time<1ms TTL=125
Ping statistics for 172.12.345.67:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 0ms, Maximum = 0ms, Average = 0ms
If you are unable to successfully ping the server machine (and have confirmed that the firewall rules for that machine allow pings), contact your IT admin.
Check Ports
If you are able to ping the server machine from a client but still unable to access the webapps homepage, there may be an issue with the specific port used by the server. To check this, run the following command in Windows Powershell with the FQDN and port of your server:
tnc -computer hostname.mydomain.com -port 9988
You should receive a response like the following:
ComputerName : hostname.mydomain.com
RemoteAddress : 172.12.345.67
RemotePort : 9988
InterfaceAlias : Ethernet 4
SourceAddress : 172.10.987.65
TcpTestSucceeded : True
If not, check with your IT admin to confirm that your server's security settings and firewall allow traffic on the port used by MATLAB Web App Server.
Contact MathWorks Support
If all of these tests succeed and you are still unable to connect to the webapps homepage from a supported browser on a client machine, reach out to MathWorks Support for further assistance.
