The Domain Name System (DNS) debug function can provide information that can help you determine and correct DNS server problems.
DNS offers 12 levels of debug control. Logging typically provides an easier method of finding problems, but in some cases debugging might be necessary. Under normal conditions, debugging is turned off (value = 0). IBM recommends that you first use logging to attempt to correct problems.
Valid debug levels are 0 through 11. Your IBM® service representative can help you determine the appropriate debug value for diagnosing your DNS problem. Values of 1 or higher write debug information to the NAMED.RUN file in your i5/OS® directory path: Integrated File System/Root/QIBM/UserData/OS400/DNS/<server instance>, where <server instance> is the name of the DNS server instance. The NAMED.RUN file continues to grow as long as the debug level is set to 1 or higher, and the DNS server continues to run. You can also use the Server Properties - Channels page to specify preferences for maximum size and number of versions of the NAMED.RUN file.
To change the debug value for a DNS server instance, follow these steps:
Changes to the debug level do not take effect while the server is running. The debug level set here will be used the next time the server is fully restarted. If you need to change the debug level while the server is running, see Advanced DNS features.
Related concepts
Advanced Domain Name System features