Solaris 10g RAC Clusterware Raw device dd comand block size, sizing

Question

Hi
We are in the process of installing clusterware for RAc on solaris 10. I have 4 luns 500mb each, we want to use them for the voting disks and ocr,
1. Which one do we use /dev/dsk or /dev/rdsk?
2) Also how do you erase the data to clear them out, I think you use the dd comand correct, but what is the full sytax to cllear the voiting disk and the ocr, do I need to specify a block size ??
3) Somebody was saying I should label the disks, just incase the controllers change the numbering if they ever get reconfigured, can this be done in SUN Solaris, if so can you give me an example, and do I specify the label as the ocr path??
Thanks
For all the info.

Answer 1

1. Which one do we use /dev/dsk or /dev/rdsk?
$$
Please use Character Device ,This is general practice. However from 10.2.0.1 Block Device can also work.
# chown oracle:dba /dev/rdsk/cxtydzs6
# chmod 660 /dev/rdsk/cxtydzs6
2) Also how do you erase the data to clear them out, I think you use the dd comand correct, but what is the full sytax to cllear the voiting disk and the ocr, do I need to specify a block size ??
$$
do
dd if=/dev/zero of=/dev/ocr_disk$i bs=8192 count=25000 &
done
3) Somebody was saying I should label the disks, just incase the controllers change the numbering if they ever get reconfigured, can this be done in SUN Solaris, if so can you give me an example, and do I specify the label as the ocr path??
$$
Oracle recommends that you use a file name similar to dbname_raw.conf for this file.
The following example shows a sample mapping file for a two-instance RAC cluster. Some of the partitions use alternative symbolic link names. Make sure that the partition device file name that you specify identifies the same partition on all nodes.
system=/dev/rdsk/c2t1d1s3
sysaux=/dev/rdsk/c2t1d1s4
example=/dev/rdsk/c2t1d1s5
users=/dev/rdsk/c2t1d1s6
temp=/dev/rdsk/c2t1d2s3
undotbs1=/dev/rdsk/c2t1d2s4
undotbs2=/dev/rdsk/c2t1d2s5
redo1_1=/dev/rdsk/c2t1d2s6
redo1_2=/dev/rdsk/c2t1d3s3
redo2_1=/dev/rdsk/c2t1d3s4
redo2_2=/dev/rdsk/c2t1d3s5
control1=/dev/rdsk/c2t1d4s3
control2=/dev/rdsk/c2t1d4s3
spfile=/dev/rdsk/dbname_spfile_raw_5m
pwdfile=/dev/rdsk/dbname_pwdfile_raw_5m
Hope this will help..
Bharat
NS