The bugs section of dumpon(8) states: Dumpon currently allows only devices with minor number 1 to be used as dump devices. This is obviously no longer true. Various messages on the mailing lists show that people have been dumping to /dev/da0s1b (minor 0x20001) with good effect. The bugs section does not mention that setting DUMPDEV in rc.conf causes dumpon to be called during the transition from single-user to multi-user. This means that it's close to impossible to capture dumps caused by problem during boot. There was a discussion on -current about this problem in March 2000 (see revision 1.12 of this file). The problem has not been resolved yet (AFAIK), so bugs should warn about it. Additionally, a part of the notes section should be changed. Old version: One of the system swap devices is usually chosen as the dump device, as swap devices are the most likely to have the required space at dump time. New version: One of the system swap devices should be used as the dump device. Devices used for regular filesystems will probably lack sufficent space to store the dump. [And that's the polite version - I was tempted to write to something to the effect of "using anything but a swap device is suicidal"] Fix: The patch implements the changes outlined above. The changes should be MFCed to RELENG_4 before 4.1-RELEASE. How-To-Repeat: man 8 dumpon dumpon /dev/any-swap-device put DUMPEV=above-device in rc.conf panic the system, reboot => core is saved in /var/crash
Responsible Changed From-To: freebsd-doc->ben I'll commit this tonight.
State Changed From-To: open->closed Committed in -current and 4-stable, thanks!