dap · September 14, 2009 18:36
diff --git a/gistfile1.txt b/gistfile1.txt
 How to debug an Apache segfault on Solaris 10

 1.  Ensure that the /var/core directory exists.

 2.  $ mdb /usr/local/sbin/httpd

 3.  At the MDB prompt:
    > ::run -X
    The "-X" above is actually a parameter to the httpd binary.

 4.  Do whatever makes it segfault.

 5.  Get a stack dump from mdb:
    > ::stack

 6.  Fix your shit up.

 mdb will follow forks, so when Apache forks a child process to handle the request,
 you can opt to follow that or stay with the parent.  Likewise, if Apache goes to
 invoke a CGI, you can opt to follow the CGI.  Very useful.  "::dcmds" will show
 additional commands which can be run such as "::getenv", "::stackregs", "::nm",
 "::objects", and "::mappings".  Word.
	How to debug an Apache segfault on Solaris 10

	1. Ensure that the /var/core directory exists.

	2. $ mdb /usr/local/sbin/httpd

	3. At the MDB prompt:
	> ::run -X
	The "-X" above is actually a parameter to the httpd binary.

	4. Do whatever makes it segfault.

	5. Get a stack dump from mdb:
	> ::stack

	6. Fix your shit up.

	mdb will follow forks, so when Apache forks a child process to handle the request,
	you can opt to follow that or stay with the parent. Likewise, if Apache goes to
	invoke a CGI, you can opt to follow the CGI. Very useful. "::dcmds" will show
	additional commands which can be run such as "::getenv", "::stackregs", "::nm",
	"::objects", and "::mappings". Word.