[DRBD-user] Limits to number of devices ?

[Ralf Gross]

Denis PETIT schrieb:
> 
> I'm trying to configure DRBD 0.7.21 on a kernel 2.6.16-2 (by
> kernel-patch), on a Debian etch machine.
> 
> I'm succeeding at configuring /dev/drbd0 to /dev/drbd7, but for each
> device i try to configure after /dev/drbd7, i have a :
> "can not open /dev/drbd8: No such device or address"
> 
> I create with mknod the /dev/drbd i need and i'm there :
> brw-rw---- 1 root disk 147,  0 2006-10-27 17:40 /dev/drbd0
> brw-rw---- 1 root disk 147,  1 2006-10-27 17:40 /dev/drbd1
> brw-rw---- 1 root disk 147, 10 2006-10-27 17:46 /dev/drbd10
> brw-rw---- 1 root disk 147, 11 2006-10-27 17:46 /dev/drbd11
> brw-rw---- 1 root disk 147, 12 2006-10-27 17:46 /dev/drbd12
> brw-rw---- 1 root disk 147, 13 2006-10-27 17:46 /dev/drbd13
> brw-rw---- 1 root disk 147, 14 2006-10-27 17:46 /dev/drbd14
> brw-rw---- 1 root disk 147, 15 2006-10-27 17:46 /dev/drbd15
> brw-rw---- 1 root disk 147,  2 2006-10-27 17:40 /dev/drbd2
> brw-rw---- 1 root disk 147,  3 2006-10-27 17:40 /dev/drbd3
> brw-rw---- 1 root disk 147,  4 2006-10-27 17:40 /dev/drbd4
> brw-rw---- 1 root disk 147,  5 2006-10-27 17:40 /dev/drbd5
> brw-rw---- 1 root disk 147,  6 2006-10-27 17:40 /dev/drbd6
> brw-rw---- 1 root disk 147,  7 2006-10-27 17:40 /dev/drbd7
> brw-rw---- 1 root disk 147,  8 2006-10-27 17:46 /dev/drbd8
> brw-rw---- 1 root disk 147,  9 2006-10-27 17:46 /dev/drbd9
> 
> As i told, the 8 first devices seem to work very fine.
> What's wrong with the next ones ?

Hm, why don't you use the minor-count paramter in the drbd.conf file?

|minor-count count
|
|count may be a number from 1 to 255.
|
|Use minor-count if you want to define more resources later without
|reloading the DRBD kernel module. Per default the module loads with
|exactly as many devices as configured in this file. Builtin default
|for module is 2, and 8 for monolithic kernel. For monolithic kernel
|minor-count is ignored, and you have to pass a kernel boot parameter
|drbd.minor_count=count to change the default.

Ralf