When a server kernel panics it abruptly halts all normal system operations. Usually,
a kernel process named panic() outputs an error message to the console and stores debugging information in nonvolitile memory to be written to a crash log file upon restarting the computer. Saving the memory contents of the core and associated debugging information is called a “core dump.”
This debugging information is highly technical, but system administrators can use this information to:
ÂÂ Record details about machines that are panicking and why.
For example, if you manage a large number of Mac OS X Servers, you might want to monitor which servers are panicking and why. You can use this information to determine how frequently kernel panics occur, whether there are common symptoms, and, most importantly, whether
ÂÂ Perform offline debugging on
If you manage a
For more information on debugging core dumps see Developer Technical Note #2118 at developer.apple.com/technotes/tn2004/tn2118.html#SECDEBUG.
You can configure a Mac OS X Server computer so that, when the machine panics, it transmits a core dump of the kernel to a remote core dump server via TCP/IP. The core dump server uses a daemon to collect the kernel core dump from the client and writes it to a file on the hard disk. You can then analyze the core dump using a variety of tools, most notably GDB.
CAUTION: The core dump of kernel memory is sent to the server in the clear. It’s possible that this data might include sensitive information. Therefore, configure your network so this data can’t be seen by unauthorized persons. For example, use switched hubs, a firewall, or a VPN.
To use a FireWire connection to transmit a core dump (a useful alternative when the kernel panic on the client involves the
The following sections contain information to set up a remote listening server, which receives core dump information from panicked computers, and to set up a server to send its core dump information to the remote listening server via TCP/IP over Ethernet.
Chapter 8 Monitoring Your System
