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RAID help on Red Hat (newbie)
| Posted by laxworld, 06-25-2008, 10:36 AM |
| Hey guys, Im running latest Red Hat on this server we just got in..
We have 20 1TB hard drives RAID 0 I believe.
when I view partitions through parted then print it says sdb1 is the 19TB partition and its in /dev/
...when I go here to find it I cant locate sdb1...
In simple terms...if we want to set up a file system to stick all our apps and files..where should I put it in the system?
Is dev allocated 19TB? or is it some sdb1 that I dont understand how to view? Im pretty bad with linux..if anyone has some suggestions on how to view folder sizes and allocations or how to somehow access this partition please let me know (or any insight as to how a RAID fully works)
Thanks in advance
Last edited by laxworld; 06-25-2008 at 10:41 AM.
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| Posted by zuborg, 06-25-2008, 10:45 AM |
| Not sure you can do it. Partition size value is 32-bit variable, which limit size of partition to 2^32*512 = 2T (512 is device block size)
Just do newfs on sdb and then mount it, without partitioning.
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| Posted by laxworld, 06-25-2008, 10:58 AM |
| its listed in /dev/ when i do parted i can view it through print command.
so you are saying i can access it if i mount it under /mnt/namehere
and then go in and mkdir and do whatever i want in there?
(i guess what im trying to ask is if i mount the drive to a specific folder under mnt the 19TB of space will then be allocated to that single directory right?)
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| Posted by recklessop, 06-25-2008, 11:00 AM |
| you will have to use 8KB block size if your using ext3 for the partition. check http://en.wikipedia.org/wiki/Ext3#Size_limits
are you using ext3 ? or something else?
also it might be easier if you partition it up a little bit. If you dont need all 20 TB in one partition. I mean just a file system check on that would probably take hours.
Im not a linux expert. But i have been using debian for about 10 years now. and when my web server checks its 5 disk (36gb) raid 5 it takes it like 15 minutes to check all the paritions. so 20TB would be a LONG dang time lol. Let me know if you have more questions
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| Posted by recklessop, 06-25-2008, 11:05 AM |
| yes it would be under that directory
such as if you do mount /dev/sdb1 /hugepartition
then do a df -h
you would get
/hugepartition 19TB 0% used 100% free etc etc or something close to that
after checking UFS v2 (file system type) can hold up like 8ZB so that would would as a file system for you too if you have UFS support on Redhat
Last edited by recklessop; 06-25-2008 at 11:13 AM.
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| Posted by laxworld, 06-25-2008, 11:10 AM |
| thank you zuborg and xaero -- this is my first year with linux so i am kind of getting baptism by fire here when a linux server shows up and they look at me and say fix it haha!
how do you specify the 8kb block size though?
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| Posted by zuborg, 06-25-2008, 11:19 AM |
| No need to specify 8k block, it will select best block size automatically.
But don't forget to enable journaling when doing 'newfs', otherwise fsck will really takes hours after crash.
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| Posted by recklessop, 06-25-2008, 11:26 AM |
| well you would use mkfs.ext3 -b 8192 /dev/sdb1 (this will FORMAT the partition with ext3 with 8192 block size .... if you system supports that large of a block size) try it and let me know (if you can format it)
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| Posted by laxworld, 06-25-2008, 11:34 AM |
| how do i specify the size of the partition using those commands (say i wished two make 2 10tb as an example)
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| Posted by recklessop, 06-25-2008, 11:35 AM |
| after trying this on my debian machine i would recommend JFS instead of ext3 because jfs supports up to 32 petabytes and you dont have to jump through hoops as much as with ext3 with large block sizes
so try mkfs.jfs /dev/sdb1
then mkdir /dir/where/u/want/it/mounted
then
mount -t jfs /dev/sdb1 /dir/u/created
then your all set with 19TB of space in that directory
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| Posted by laxworld, 06-25-2008, 11:38 AM |
| but how could i make two partitions from that 1 drive, say a 9 and a 10 tb?
i get how to mount and go from there, but how could i create 2 and specify the sizes i want?
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| Posted by recklessop, 06-25-2008, 11:40 AM |
| i use cfdisk
so cfdisk /dev/sdb
then delete the partition thats in there
then create two new partitions with type 83 (whatever is linux file system)
Last edited by recklessop; 06-25-2008 at 11:44 AM.
Reason: figured out what number it was
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| Posted by recklessop, 06-25-2008, 11:46 AM |
| should get a screen like this to pick type 83 for the linux file system type
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