Re: RAW DEVICE

Nguyen Trieu wrote: > Hello All, > I am new in Informix. Can any body show me how to set up raw device > on Solaris 2.6 > and IDS 7.3.uc5. I read the installation menu but I am confuses about > offset values. Can you point out how to calculated an offset. Thank you > > --Wayne You can set offset 0 if slice used for raw device doesn't beginning from cylinder 0, otherwice you must reserve space for disk label - at least track 0. Example for disk /dev/dsk/c0t3d0 : format> verify Primary label contents: Volume name = < > ascii name = <SUN2.1G cyl 2733 alt 2 hd 19 sec 80> pcyl = 3500 ncyl = 2733 acyl = 2 nhead = 19 nsect = 80 Part Tag Flag Cylinders Size Blocks 0 root wm 0 - 1077 800.08MB (1078/0/0) 1 unassigned wu 0 0 (0/0/0) 2 backup wu 0 - 2732 1.98GB (2733/0/0) 3 unassigned wm 0 0 (0/0/0) 4 swap wu 1078 - 1212 100.20MB (135/0/0) 5 usr wm 1213 - 1347 100.20MB (135/0/0) 6 unassigned wm 0 0 (0/0/0) 7 usr wm 1348 - 2732 1.00GB (1385/0/0) Track size is 80 / 2 = 40 Kbytes (sector size is 512). If you want to use /dev/dsk/c0t3d0s0 or (not recommended) /dev/dsk/c0t3d0s2 you must set offset at least 40 You can place more than 1 chunk into slice. For example size of /dev/dsk/c0t3d0s7 is 1385 * 80 * 19 / 2 = 1052600 Kbytes. So you can set chunk 1 offset 0 size 500000 chunk 2 offset 500000 size 552600 Hope this helps Leonid