2.4.0: Raw devices ?
Quoted 2 lines · Meino Cramer
short question: How cabn I activate/where can I find the raw devices often described as /dev/raw[12]* in/with kernel linux-2.4.0.
There doesn't seem to be any config option for raw devices in lk 2.4.0 , they are just there. However the raw (8) utility expects them in a different place from where Documentation/devices.txt currently says they are. You may have to set up these char devices:
$ ls -l /dev/rawctl crw-r--r-- 1 root root 162, 0 Jan 13 05:12 /dev/rawctl
$ ls -l /dev/raw/* crw-r--r-- 1 root root 162, 1 Jan 13 05:12 /dev/raw/raw1 crw-r--r-- 1 root root 162, 2 Jan 13 05:12 /dev/raw/raw2 crw-r--r-- 1 root root 162, 3 Jan 13 05:12 /dev/raw/raw3 crw-r--r-- 1 root root 162, 4 Jan 13 05:12 /dev/raw/raw4 etc.
Recent versions of dd meet the alignment requirements of raw devices as does lmdd (from the lmbench package). I have done some timings of disk to disk copies using raw devices compared to other devices. See:
http://www.torque.net/sg/fst_copy.html
Quoted 1 line
And where can I find the "raw" utility...
In both RH 6.2 and 7.0 the raw (8) utility is in the util-linux package (RH have applied a "raw" patch for those two lk 2.2 versions). Read man (8) raw to find out how to bind a raw device to an existing block device. Example:
$ raw /dev/raw/raw1 /dev/sda3
Doug Gilbert
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected]
Please read the FAQ at http://www.tux.org/lkml/