After a problem has been verified you should begin by carrying out a basic network test:
Local network test
Ensure that your PC is correctly connected to the local network and can connect to other networks (specifically HSCN).
- In the search bar type – command. This will bring up the command prompt box.
- In the command prompt box type – ipconfig. This will provide the IP address of your computer and your default gateway. Make a note of the IP address of your default gateway.
- Ping your default gateway. In the command prompt box type – ping x.x.x.x (where x.x.x.x is the IP address of your default gateway).
- If this fails, you have a local network connectivity issue and you need to contact your local network administrator/IT support.
HSCN connectivity test
Next, you can test connectivity to HSCN by checking if you can communicate with a common point on HSCN. With the command prompt window open type:
Ping 18.104.22.168 or ping 22.214.171.124 (these are the IP addresses of the Transition Network (TN) and HSCN DNS servers).
If these tests were successful then you are connected to HSCN. At this point you can begin testing for your specific issue.
Issue 1 - cannot connect to another network location on HSCN or the TN (IP address)
Using the command prompt window attempt to ping the IP address of your proposed destination.
If ping was unsuccessful then you need to determine how far the network traffic got before it failed.
In the command prompt window type - tracert x.x.x.x (where x.x.x.x is the IP address of the destination). A successful trace should look similar to the below:
If the trace fails to complete or a router intentionally does not respond to the Internet Control Message Protocol (ICMP) requests, then the below results will appear in the traceroute output:
Whilst ping and traceroute are rudimentary tests these results strongly indicate a routing incident, and your CNSP should be contacted to rule out a routing issue.
Note: a standard traceroute may time out in the middle due to routers intentionally not responding to the ICMP request. However, the traceroute should still reach the destination IP address. For a more comprehensive trace a Transmission Control Protocol (TCP) traceroute could be initiated, however Windows does not have a native TCP traceroute utility so advice on using a TCP traceroute falls out of the scope of this document.
Issue 2 - cannot connect to a web site, web application or web address (Uniform Resource Locator or URL) that is hosted on HSCN or the TN
Failure to connect to a web site or web application can often appear to be caused by a network issue when in fact the network is fine. This section addresses network and web related issues.
Troubleshooting connectivity to a web site is usually more challenging than isolating a connectivity issue to a network address (IP address) because ping and traceroute are tools used to communicate with a physical or virtual device and may fail even though a network path to the web site is available. This is because a URL contains the protocol, domain name and path rather than just an IP address. Therefore, IP addresses and URLs have a one to many relationship.
Check for web related issues
- Ensure that you have network connectivity to HSCN using the methods described in issue 1, above.
- Test to ensure you have connectivity to a DNS server capable of resolving the URL: in the command prompt window type – nslookup. The response should be the name and IP address of your DNS server. If nslookup fails you can ping the HSCN DNS server (126.96.36.199)
- If this fails then a potential DNS issue should be investigated, which is out of the scope of this guide. Further information is available on the HSCN/TN DNS page.
- Open another tab, or window, in your browser and see if you can communicate with another website on HSCN other than the one causing the specific issue. For example, http://nww.digital.nhs.uk/.
- If one or both web sites fail to connect then try to connect using an alternative web browser. If the connection fails on multiple browsers the browser error message should be reviewed.