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32 .\" From: @(#)swapon.8 8.1 (Berkeley) 6/5/93
40 .Nd "specify a device for crash dumps"
50 is used to specify a device where the kernel can save a crash dump in
55 normally occur from the system multi-user initialization file
59 variable in the boot time configuration file
62 The size of the specified dump device must be at least 64 KB greater
63 than the size of physical memory.
69 to be verbose about its activity.
73 condition may occur in a situation
74 where the kernel cannot trust its internal representation
75 of the state of any given filesystem,
76 one of the system swap devices,
79 a device containing a filesystem,
80 should be used as the dump device.
84 program operates by setting the
88 to the device number of the designated
92 (meaning that no dumps are to be taken) if
99 cannot be used during kernel initialization, the
103 must be used to enable dumps for system panics which occur
104 during kernel initialization.
117 .Bl -tag -width "/dev/{ad,da}?s?b" -compact
118 .It Pa /dev/{ad,da}?s?b
121 boot-time system configuration
124 Because the filesystem layer is already dead by the time a crash dump
125 is taken, it is not possible to send crash dumps directly to a file.