Specifications

Chapter 5 Connecting to an ISP
Configuring DDNS on the JACE-4/5
Niagara Release 2.3
Niagara Networking & Connectivity Guide Revised: May 22, 2002
5–25
Figure 5-8 DDNS error in browser-view of event log.
In addition to the event log, you can try the following other techniques to diagnose
problems after determining the IP address that the JACE is using.
• use ping and tracert to verify that you can ping that IP address from a
remote workstation.
• use nslookup to query DNS servers at TZO to verify that the domain name
assigned to the JACE is correctly mapped to the IP address assigned by the ISP.
Note There is often a delay in the propagation of DNS changes. That may mean that the
servers at TZO may have been updated, but the DNS servers that your workstation
uses may not have updated. Use
nslookup to query TZO and your DNS servers to
pinpoint the discrepancy, then use the IP address information at TZO to connect to
the JACE.
For more information on these troubleshooting commands, see the “Connectivity
Troubleshooting Utilities” section on page 2-19.
Trouble-
shooting Update
Failures
If the JACE-4/5 is unable to update its DDNS entry, remote users will not be able to
access it via domain name. It may be connected to the Internet, but its current address
is unknown.