sco unix boot loader creation?

[onlineravee]

hi,
i had installed the sco unix 5.0.5,the boot loader doesn't install properly,when i restart the machine cycl over error is given. when i boot through floppy, it works through hard disk it not work.
how can i install the bootloader in my system?



ravi

 

[pcunix]

Install it under the 1023rd cylinder.

SCO Unix questions are more exposed to SCO knowledgable folk if you use the SCO forum rather than this next time.
Tony Lawrence
SCO Unix/Linux Resources

http://pcunix.com

tony@pcunix.com

 

[edfair]

You probably would be better off reloading into a partition where everything fits under the 1023.
If you fix it now without correcting the problem you will probably be bit again. Ed Fair
efair@atlnet.com

Any advice I give is my best judgement based on my interpretation of the facts you supply.

Help increase my knowledge by providing some feedback, good or bad, on any advice I have given.

 

[pcunix]

It's not at all necessary to load everything under 1023. The only concern is the boot partition.

Tony Lawrence
SCO Unix/Linux Resources

http://pcunix.com

tony@pcunix.com

 

[pcunix]

I was sloppy above. What I should have said is that only the boot FILESYSTEM needs to be below 1023 cylinders (and technically, that's a bios problem, not a Unix problem).

SCO systems (unlike Linux systems) generally use ONE partition that is divided into multiple filesystems.

It is not necessary that the fdisk partition be kept under 1023 cylinders as long as the boot filesystem won't extend beyond 1023. Of course if your entire partition is under 1023, the boot filesystem would obviously meet that criteria also. But it does help to know that the boot filesystem will be created first, so if the partition starts under cylinder 1023 and the size allocated for boot won't take it beyond 1023, you'll be fine.


And again- this question should have been in the SCO forum, not here.
Tony Lawrence
SCO Unix/Linux Resources

http://pcunix.com

tony@pcunix.com

 

[onlineravee]

to all,
tell how to do it on that exact 1023 location on hdd.?
ravi
onlineravee@yahoo.com

 

[pcunix]

Do the math.

You know (or can find ot ) the geometry of the disk- cylinders, heads, sectors per track.

There are 512 bytes per sector (could be different but that's the norm)

Let's say your drive is 4464 cylinders by 255 heads by 63 sectors per track. Thats a 36 GB drive (roughly).

(everything is rough because some percentage of the drive is reserved for diagnostics, bad tracks etc.)

The total sectors are around 72 million give or take.

Where does the 1023 cylinder fall?

It's at the 1023 * 255 * 63 sector, roughly 16.4 million sectors from the beginning. You can also see that in GB, that's about 1/4 (it's 1024/4464) of the total capacity- about 8 GB.

So if the first partition were over 8 GB or 16 million sectors, that's going to push the second partition beyond the 1023 cylinder.

Note that the sector you pick to end a partition needs to be on a head boundary- in other words, it has to be evenly divisible by the number of heads.


Tony Lawrence
SCO Unix/Linux Resources

http://pcunix.com

tony@pcunix.com