[CentOS] I need storage server advice

2008-05-06 Thread Ed Morrison

Hi:

I need advice on implementing a storage server.  I really do not have 
the $ to spend for a Dell iSCSI storage divice and I am thinking 
trunning CentOS 5.x with ftp or FreeNAS.  Here is what I am looking at 
and concerned about.


Situation:
My current storage needs are approximately 1.5 TB annually.  This will 
increase to about 3.5 TB annually over the next 5 years (rough est.).  
This box will just be a data archive and once it is full it will only be 
used very infrequently if not used at all. Files are small up to 10 MB 
but numerous.


CentOS:
Upgrading to the newer CentOS flavors.  I will not have the ability to 
archive this data to tape and I am concerned about loosing the data when 
upgrading the OS.  How best to handle this?


Storage limitation.  It is my understanding that there is a 2 TB storage 
limitation with Linux (and windows) in general particularly for 
stability.  I see that ReiserFS can go up to 16 TB.  Is any one using 
this?  If so, how has it been for you?



FreeNAS
Anyone using FreeNAS?  What is your experience?  How easy is it to add 
new drives and keep your data?  Upgrading to newer versions?


Thanks,

Ed
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Re: [CentOS] I need storage server advice

2008-05-06 Thread Joshua Baker-LePain

On Tue, 6 May 2008 at 12:11pm, Ed Morrison wrote


Situation:
My current storage needs are approximately 1.5 TB annually.  This will 
increase to about 3.5 TB annually over the next 5 years (rough est.).  This 
box will just be a data archive and once it is full it will only be used very 
infrequently if not used at all. Files are small up to 10 MB but numerous.


CentOS:
Upgrading to the newer CentOS flavors.  I will not have the ability to 
archive this data to tape and I am concerned about loosing the data when 
upgrading the OS.  How best to handle this?


You have to be careful, but it's quite easy to leave partitions (and thus 
their data) alone when you are updating/reinstalling the OS.


Storage limitation.  It is my understanding that there is a 2 TB storage 
limitation with Linux (and windows) in general particularly for stability.  I 
see that ReiserFS can go up to 16 TB.  Is any one using this?  If so, how has 
it been for you?


You cannot boot from a device larger than 2TiB, but that's the only 
limitation at that size.  I run several multi-TB servers (including over 
8TB) on CentOS-5 with no issues (using ext3).


You do not want to use ReiserFS.  It's not supported under CentOS, and 
it's future is far less than certain (and I do not want to restart *that* 
OT conversation).  ext3 is the default FS under CentOS and works pretty 
well.


--
Joshua Baker-LePain
QB3 Shared Cluster Sysadmin
UCSF
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Re: [CentOS] I need storage server advice

2008-05-06 Thread Matt Shields
On Tue, May 6, 2008 at 3:11 PM, Ed Morrison [EMAIL PROTECTED] wrote:
 Hi:

  I need advice on implementing a storage server.  I really do not have the $
 to spend for a Dell iSCSI storage divice and I am thinking trunning CentOS
 5.x with ftp or FreeNAS.  Here is what I am looking at and concerned about.

  Situation:
  My current storage needs are approximately 1.5 TB annually.  This will
 increase to about 3.5 TB annually over the next 5 years (rough est.).  This
 box will just be a data archive and once it is full it will only be used
 very infrequently if not used at all. Files are small up to 10 MB but
 numerous.

  CentOS:
  Upgrading to the newer CentOS flavors.  I will not have the ability to
 archive this data to tape and I am concerned about loosing the data when
 upgrading the OS.  How best to handle this?

  Storage limitation.  It is my understanding that there is a 2 TB storage
 limitation with Linux (and windows) in general particularly for stability.
 I see that ReiserFS can go up to 16 TB.  Is any one using this?  If so, how
 has it been for you?


  FreeNAS
  Anyone using FreeNAS?  What is your experience?  How easy is it to add new
 drives and keep your data?  Upgrading to newer versions?

  Thanks,

  Ed

I haven't used this and maybe I understand the concept, but what about
RedHat's GFS?  From what has been told to me, you take a cluster of
servers and it turns them into a large disk array.  Someone correct me
if I'm wrong.

-- 
-matt
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Re: [CentOS] I need storage server advice

2008-05-06 Thread Scott Thistle
Actually, I am on rh436 course now. Why not set up centos51 as iscsi
target itself?


On 5/6/08, Matt Shields [EMAIL PROTECTED] wrote:
 On Tue, May 6, 2008 at 3:11 PM, Ed Morrison [EMAIL PROTECTED]
 wrote:
  Hi:
 
   I need advice on implementing a storage server.  I really do not have the
 $
  to spend for a Dell iSCSI storage divice and I am thinking trunning CentOS
  5.x with ftp or FreeNAS.  Here is what I am looking at and concerned
 about.
 
   Situation:
   My current storage needs are approximately 1.5 TB annually.  This will
  increase to about 3.5 TB annually over the next 5 years (rough est.).
 This
  box will just be a data archive and once it is full it will only be used
  very infrequently if not used at all. Files are small up to 10 MB but
  numerous.
 
   CentOS:
   Upgrading to the newer CentOS flavors.  I will not have the ability to
  archive this data to tape and I am concerned about loosing the data when
  upgrading the OS.  How best to handle this?
 
   Storage limitation.  It is my understanding that there is a 2 TB storage
  limitation with Linux (and windows) in general particularly for stability.
  I see that ReiserFS can go up to 16 TB.  Is any one using this?  If so,
 how
  has it been for you?
 
 
   FreeNAS
   Anyone using FreeNAS?  What is your experience?  How easy is it to add
 new
  drives and keep your data?  Upgrading to newer versions?
 
   Thanks,
 
   Ed

 I haven't used this and maybe I understand the concept, but what about
 RedHat's GFS?  From what has been told to me, you take a cluster of
 servers and it turns them into a large disk array.  Someone correct me
 if I'm wrong.

 --
 -matt
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Re: [CentOS] I need storage server advice

2008-05-06 Thread John R Pierce

Ed Morrison wrote:

Hi:

I need advice on implementing a storage server.  I really do not have 
the $ to spend for a Dell iSCSI storage divice and I am thinking 
trunning CentOS 5.x with ftp or FreeNAS.  Here is what I am looking at 
and concerned about.


Situation:
My current storage needs are approximately 1.5 TB annually.  This will 
increase to about 3.5 TB annually over the next 5 years (rough est.).  
This box will just be a data archive and once it is full it will only 
be used very infrequently if not used at all. Files are small up to 10 
MB but numerous.




infrastructure to support lots of SATA drives isn't real cheap 
regardless.   you really don't want to just bolt a bunch of drives up 
inside a jumbo desktop tower and call it a server. 5 years at that 
run rate is going to be something like 12TB total storage, which using 
commodity 500GB SATA drives in raid10 will take around 48 drives.   
Thats a lot of SATA channels...


With that many spindles, you'll also want to allocate several hot spares.

I dislike raid5 for a number of reasons, and would recommend sticking 
with mirroring, eg raid1 or raid10.   You /never/ want to build a raid5 
much over about 6-8 disks, or the raid rebuild times get ridiculous and 
double drive failures will lose huge amounts of storage.



hey, have you considered the Sun x4500 ?  its a 4U(?) dual dualcore 
opteron server that comes with 48 x 500GB SATA drives. ***




CentOS:
Upgrading to the newer CentOS flavors.  I will not have the ability to 
archive this data to tape and I am concerned about loosing the data 
when upgrading the OS.  How best to handle this?


as others have said, as long as your critical data is on seperate file 
systems, there should be no issue here.


Storage limitation.  It is my understanding that there is a 2 TB 
storage limitation with Linux (and windows) in general particularly 
for stability.  I see that ReiserFS can go up to 16 TB.  Is any one 
using this?  If so, how has it been for you?




since your data is archival in nature, it really shouldn't be that hard 
to manage it as multiple 2 TB chunks on seperate file systems.   when 
you fill 2TB, take 8 x 500GB more SATA drives, raid10 them, and mount 
them as another file system, /u01, /u02, keep an index file 
somewhere which logs which backups are where.





FreeNAS
Anyone using FreeNAS?  What is your experience?  How easy is it to add 
new drives and keep your data?  Upgrading to newer versions?


I setup OpenFiler once, that worked quite nicely, supported NFS, SMB, 
and iSCSI, and was pretty easy to use.   I'd have to assume FreeNAS is 
similar.




*** heresy (for this list), Solaris 10, with its ZFS file system, is 
extremely good at handling very large storage configurations like this.

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Re: [CentOS] I need storage server advice

2008-05-06 Thread John R Pierce

Scott Thistle wrote:

Actually, I am on rh436 course now. Why not set up centos51 as iscsi
target itself?
  


that just pushes the file management issues off to another system, where 
you still have to solve them


he wants an archive server, which is more of a NAS device then a SAN.   
iSCSI addresses the SAN space, providing flexible block storage to 
multiple systems



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Re: [CentOS] I need storage server advice

2008-05-06 Thread Les Mikesell

Ed Morrison wrote:


I need advice on implementing a storage server.  I really do not have 
the $ to spend for a Dell iSCSI storage divice and I am thinking 
trunning CentOS 5.x with ftp or FreeNAS.  Here is what I am looking at 
and concerned about.


Situation:
My current storage needs are approximately 1.5 TB annually.  This will 
increase to about 3.5 TB annually over the next 5 years (rough est.).  
This box will just be a data archive and once it is full it will only be 
used very infrequently if not used at all. Files are small up to 10 MB 
but numerous.


First consider whether you can organize this into 1 TB or smaller 
partitions that are mounted separately.  If you can do that, growing the 
space is trivial - and you get the advantage that you can do raid1 
mirrors of individual drives which gives you the ability to recover data 
from any single disk.



CentOS:
Upgrading to the newer CentOS flavors.  I will not have the ability to 
archive this data to tape and I am concerned about loosing the data when 
upgrading the OS.  How best to handle this?


Don't put the permanent storage on your system drive(s) at all. Add one 
or more directories after installation and mount the additional 
partitions or raid arrays there.  Then if you do a new install, just 
uncheck the devices as disks that can be used for the system and add the 
mount points back when it is done.   But, there are lots of other ways 
to lose data.  If you'd need it after a building fire/flood or operator 
error you should build two of these and rsync to somewhere offsite.


Storage limitation.  It is my understanding that there is a 2 TB storage 
limitation with Linux (and windows) in general particularly for 
stability. 


I think that's 8TB if you don't boot from it.  But that's per mounted 
filesystem - if you can have smaller separate partitions, it won't matter.



FreeNAS
Anyone using FreeNAS?  What is your experience?  How easy is it to add 
new drives and keep your data?  Upgrading to newer versions?


You might look at openfiler if you want an appliance.

--
  Les Mikesell
   [EMAIL PROTECTED]
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Re: [CentOS] I need storage server advice

2008-05-06 Thread Les Mikesell

John R Pierce wrote:
 
infrastructure to support lots of SATA drives isn't real cheap 
regardless.   you really don't want to just bolt a bunch of drives up 
inside a jumbo desktop tower and call it a server. 5 years at that 
run rate is going to be something like 12TB total storage, which using 
commodity 500GB SATA drives in raid10 will take around 48 drives.   
Thats a lot of SATA channels...


1TB drives are available now.  5 years from now, who knows?

since your data is archival in nature, it really shouldn't be that hard 
to manage it as multiple 2 TB chunks on seperate file systems.   when 
you fill 2TB, take 8 x 500GB more SATA drives, raid10 them, and mount 
them as another file system, /u01, /u02, keep an index file 
somewhere which logs which backups are where.


If it's really rarely used and you have a sensible scheme to find it you 
could just have a drawer full of inexpensive external 1TB drives that 
you can plug in on demand, using USB, firewire, or sata connections.


--
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[EMAIL PROTECTED]

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Re: [CentOS] I need storage server advice

2008-05-06 Thread Jason
I just purchased an equallogic SAN with 16 1TB drives for 52k at work.
Love it, scheduled snapshots, thin provisioning, iscsi only but fairly
swift at 16 spindles in a RAID 50.

Jason
www.cyborgworkshop.org


John R Pierce wrote:
 Ed Morrison wrote:
 Hi:

 I need advice on implementing a storage server.  I really do not have
 the $ to spend for a Dell iSCSI storage divice and I am thinking
 trunning CentOS 5.x with ftp or FreeNAS.  Here is what I am looking at
 and concerned about.

 Situation:
 My current storage needs are approximately 1.5 TB annually.  This will
 increase to about 3.5 TB annually over the next 5 years (rough est.). 
 This box will just be a data archive and once it is full it will only
 be used very infrequently if not used at all. Files are small up to 10
 MB but numerous.

 
 infrastructure to support lots of SATA drives isn't real cheap
 regardless.   you really don't want to just bolt a bunch of drives up
 inside a jumbo desktop tower and call it a server. 5 years at that
 run rate is going to be something like 12TB total storage, which using
 commodity 500GB SATA drives in raid10 will take around 48 drives.  
 Thats a lot of SATA channels...
 
 With that many spindles, you'll also want to allocate several hot spares.
 
 I dislike raid5 for a number of reasons, and would recommend sticking
 with mirroring, eg raid1 or raid10.   You /never/ want to build a raid5
 much over about 6-8 disks, or the raid rebuild times get ridiculous and
 double drive failures will lose huge amounts of storage.
 
 
 hey, have you considered the Sun x4500 ?  its a 4U(?) dual dualcore
 opteron server that comes with 48 x 500GB SATA drives. ***
 
 
 CentOS:
 Upgrading to the newer CentOS flavors.  I will not have the ability to
 archive this data to tape and I am concerned about loosing the data
 when upgrading the OS.  How best to handle this?

 as others have said, as long as your critical data is on seperate file
 systems, there should be no issue here.
 
 Storage limitation.  It is my understanding that there is a 2 TB
 storage limitation with Linux (and windows) in general particularly
 for stability.  I see that ReiserFS can go up to 16 TB.  Is any one
 using this?  If so, how has it been for you?

 
 since your data is archival in nature, it really shouldn't be that hard
 to manage it as multiple 2 TB chunks on seperate file systems.   when
 you fill 2TB, take 8 x 500GB more SATA drives, raid10 them, and mount
 them as another file system, /u01, /u02, keep an index file
 somewhere which logs which backups are where.
 
 

 FreeNAS
 Anyone using FreeNAS?  What is your experience?  How easy is it to add
 new drives and keep your data?  Upgrading to newer versions?
 
 I setup OpenFiler once, that worked quite nicely, supported NFS, SMB,
 and iSCSI, and was pretty easy to use.   I'd have to assume FreeNAS is
 similar.
 
 
 
 *** heresy (for this list), Solaris 10, with its ZFS file system, is
 extremely good at handling very large storage configurations like this.
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RE: [CentOS] I need storage server advice

2008-05-06 Thread Ross S. W. Walker
Ed Morrison wrote:
 
 Hi:
 
 I need advice on implementing a storage server.  I really do not have 
 the $ to spend for a Dell iSCSI storage divice and I am thinking 
 trunning CentOS 5.x with ftp or FreeNAS.  Here is what I am looking at 
 and concerned about.
 
 Situation:
 My current storage needs are approximately 1.5 TB annually. This will 
 increase to about 3.5 TB annually over the next 5 years (rough est.).  
 This box will just be a data archive and once it is full it will only be 
 used very infrequently if not used at all. Files are small up to 10 MB 
 but numerous.

Well that's a hell of a lot of storage for a cheap project. Instead of
a Dell MD3000 appliance try a Dell 860 1u server (Quad Xeon) with the
LSI PERC 5e 256/512MB RAID controller there you can chain up to 3
MD1000 JBOD SATA enclosures to it. It can handle mixed SAS/SATA drives
and can hold 45 spindles across 3 enclosures per 1u server.

The 1u device will be a SPOF but you wanted cheap...

 CentOS:
 Upgrading to the newer CentOS flavors.  I will not have the ability to 
 archive this data to tape and I am concerned about loosing the data when 
 upgrading the OS.  How best to handle this?

With the 1u server you can always upgrade the OS as the data is stored
externally. Hell you can even swap out the 1u 860 for say a 2u 2950
as needs grow which gives better redundancy as well as internal storage
for snapshots or some other use. Just get the 860 with 2x250GB drives,
and create a software mirror out of them. You can always break the mirror,
upgrade the OS and if it works re-mirror, otherwise boot the old half
and re-mirror.

 Storage limitation.  It is my understanding that there is a 2 TB storage 
 limitation with Linux (and windows) in general particularly for 
 stability.  I see that ReiserFS can go up to 16 TB.  Is any one using 
 this?  If so, how has it been for you?

ext3 can go up to 8TB, xfs and jfs can go up to 1EB which should hold
you.

 
 FreeNAS
 Anyone using FreeNAS?  What is your experience?  How easy is it to add 
 new drives and keep your data?  Upgrading to newer versions?

You can also check out OpenFiler which has NAS and iSCSI included.

-Ross

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Re: [CentOS] I need storage server advice

2008-05-06 Thread Michael Semcheski
On Tue, May 6, 2008 at 3:11 PM, Ed Morrison [EMAIL PROTECTED]
wrote:

 Situation:
 My current storage needs are approximately 1.5 TB annually.  This will
 increase to about 3.5 TB annually over the next 5 years (rough est.).  This
 box will just be a data archive and once it is full it will only be used
 very infrequently if not used at all. Files are small up to 10 MB but
 numerous.


The solution I found best was to buy a 2U server that has 8*750GB disks,
though they'd probably be 1TB today.  Put the disks into a RAID 5 or 6.
Using hardware RAID, divvy them up into one 50GB drive, and one really large
drive.  Put the OS on the 50GB drive, mount the really big drive.

Now you have a 50GB drive and a 7*750-50 drive.  When you fill that up, just
buy another 2U server.  When you do fill it up, the next one will be cheaper
and or bigger.

The keys to this type of setup are:
1) Don't buy storage you'll need next year today.  The best time to buy this
kind of hardware is right before you need it.
2) Look at the overall cost per gigabyte.  That's the metric that drives
things.
3) Understand your tolerance for downtime and data protection.  If you have
another copy, or a backup, and its not mission critical data, its much
cheaper not to waste disks on redundancy.

We have tape backups of our systems, and factoring in the cost of tape and
other costs, its still possible to get storage with a marginal cost below $1
/ GB.  That includes a 3 year warranty, quad core processor, 4GB of RAM
which you can probably put to use elsewhere.
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Re: [CentOS] I need storage server advice

2008-05-06 Thread Jason
I just posted this on my website, oddly enough.   While you need to
really understand your storage requirements to make an informed choice
between hardware or software RAID, with quad core CPUs being as cheap as
they are it's hard to not make the argument for software.
This is just hdparm over an average of 5 runs each on very similar
machines.

5 disc SAS array with 136g 10k drives and a hardware controller

Timing cached reads: 13336 MB in 2.00 seconds = 6673.96 MB/sec
Timing buffered disk reads: 98 MB in 1.18 seconds = 83.31 MB/sec

4 disc RAID 5 with 3Ware 9650SE and 500g 7200RPM drives

Timing cached reads: 6576 MB in 2.00 seconds = 3293.08 MB/sec
Timing buffered disk reads: 448 MB in 3.00 seconds = 149.20 MB/sec

Single 500g 7200 RPM SATA drive

Timing cached reads: 14220 MB in 2.00 seconds = 7119.78 MB/sec
Timing buffered disk reads: 198 MB in 3.02 seconds = 65.51 MB/sec

6 500g 7200 RPM SATA drives in a software RAID 5 array

Timing cached reads: 14364 MB in 2.00 seconds = 7191.86 MB/sec
Timing buffered disk reads: 852 MB in 3.00 seconds = 283.64 MB/sec

Jason
www.cyborgworkshop.org


Michael Semcheski wrote:
 On Tue, May 6, 2008 at 3:11 PM, Ed Morrison [EMAIL PROTECTED]
 mailto:[EMAIL PROTECTED] wrote:
 
 Situation:
 My current storage needs are approximately 1.5 TB annually.  This
 will increase to about 3.5 TB annually over the next 5 years (rough
 est.).  This box will just be a data archive and once it is full it
 will only be used very infrequently if not used at all. Files are
 small up to 10 MB but numerous.
 
 
 The solution I found best was to buy a 2U server that has 8*750GB disks,
 though they'd probably be 1TB today.  Put the disks into a RAID 5 or 6. 
 Using hardware RAID, divvy them up into one 50GB drive, and one really
 large drive.  Put the OS on the 50GB drive, mount the really big drive. 
 
 Now you have a 50GB drive and a 7*750-50 drive.  When you fill that up,
 just buy another 2U server.  When you do fill it up, the next one will
 be cheaper and or bigger.
 
 The keys to this type of setup are:
 1) Don't buy storage you'll need next year today.  The best time to buy
 this kind of hardware is right before you need it.
 2) Look at the overall cost per gigabyte.  That's the metric that drives
 things.
 3) Understand your tolerance for downtime and data protection.  If you
 have another copy, or a backup, and its not mission critical data, its
 much cheaper not to waste disks on redundancy.
 
 We have tape backups of our systems, and factoring in the cost of tape
 and other costs, its still possible to get storage with a marginal cost
 below $1 / GB.  That includes a 3 year warranty, quad core processor,
 4GB of RAM  which you can probably put to use elsewhere.
 
 
 
 
 
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Re: [CentOS] I need storage server advice

2008-05-06 Thread Ross S. W. Walker

Take these benchmarks with a grain of salt.

We don't know how these hardware controllers were setup and by the numbers 
posted, not very well, or they are not very good.

A SATA and a SAS drive will have roughly the same sequential io performance. 
Where SAS shines is in random io. So if it's archive, buy SATA.

65MB/s is roughly what you will see with a single SAS or SATA drive on reads, 
around 30MB/s for writes.

Sequential io is measured in MB/s and random io in IOPS or ios per second.

Each spindle in a stripe set will roughly add 50% perf to sequential io and add 
to the IOPS by the IOPS of the spindle (IOPS+IOPS...). A mirror counts as 1 
spindle for reads and 1/2 a spindle for writes (unless RAID is capable of doing 
parallel reads then it counts as 1 1/2 of reads). A RAID 5 is always one less 
spindle due to parity and each spindle on writes counts as 1/#spindles 
(write-back cache helps lessen that hurt).

For 4k sequential ios (larger block sizes will post larger numbers).

1 spindle = 65MB/s and 175 IOPS
2 spindles = 97.5MB/s and 350 IOPS
3 spindles = 146.25MB/s and 525 IOPS
4 spindles = 219.375MB/s and 700 IOPS

(175 IOPS is from 15K SAS with 3.5ms read seek and 2ms avg latency, figure 80 
IOPS for good SATA drive)

Now any performance below those numbers is a failure of the RAID system and any 
performance above those numbers is due to caching and read-ahead.

I hope that helps.

-Ross


- Original Message -
From: [EMAIL PROTECTED] [EMAIL PROTECTED]
To: CentOS mailing list centos@centos.org
Sent: Tue May 06 17:20:16 2008
Subject: Re: [CentOS] I need storage server advice

I just posted this on my website, oddly enough.   While you need to
really understand your storage requirements to make an informed choice
between hardware or software RAID, with quad core CPUs being as cheap as
they are it's hard to not make the argument for software.
This is just hdparm over an average of 5 runs each on very similar
machines.

5 disc SAS array with 136g 10k drives and a hardware controller

Timing cached reads: 13336 MB in 2.00 seconds = 6673.96 MB/sec
Timing buffered disk reads: 98 MB in 1.18 seconds = 83.31 MB/sec

4 disc RAID 5 with 3Ware 9650SE and 500g 7200RPM drives

Timing cached reads: 6576 MB in 2.00 seconds = 3293.08 MB/sec
Timing buffered disk reads: 448 MB in 3.00 seconds = 149.20 MB/sec

Single 500g 7200 RPM SATA drive

Timing cached reads: 14220 MB in 2.00 seconds = 7119.78 MB/sec
Timing buffered disk reads: 198 MB in 3.02 seconds = 65.51 MB/sec

6 500g 7200 RPM SATA drives in a software RAID 5 array

Timing cached reads: 14364 MB in 2.00 seconds = 7191.86 MB/sec
Timing buffered disk reads: 852 MB in 3.00 seconds = 283.64 MB/sec

Jason
www.cyborgworkshop.org


Michael Semcheski wrote:
 On Tue, May 6, 2008 at 3:11 PM, Ed Morrison [EMAIL PROTECTED]
 mailto:[EMAIL PROTECTED] wrote:
 
 Situation:
 My current storage needs are approximately 1.5 TB annually.  This
 will increase to about 3.5 TB annually over the next 5 years (rough
 est.).  This box will just be a data archive and once it is full it
 will only be used very infrequently if not used at all. Files are
 small up to 10 MB but numerous.
 
 
 The solution I found best was to buy a 2U server that has 8*750GB disks,
 though they'd probably be 1TB today.  Put the disks into a RAID 5 or 6. 
 Using hardware RAID, divvy them up into one 50GB drive, and one really
 large drive.  Put the OS on the 50GB drive, mount the really big drive. 
 
 Now you have a 50GB drive and a 7*750-50 drive.  When you fill that up,
 just buy another 2U server.  When you do fill it up, the next one will
 be cheaper and or bigger.
 
 The keys to this type of setup are:
 1) Don't buy storage you'll need next year today.  The best time to buy
 this kind of hardware is right before you need it.
 2) Look at the overall cost per gigabyte.  That's the metric that drives
 things.
 3) Understand your tolerance for downtime and data protection.  If you
 have another copy, or a backup, and its not mission critical data, its
 much cheaper not to waste disks on redundancy.
 
 We have tape backups of our systems, and factoring in the cost of tape
 and other costs, its still possible to get storage with a marginal cost
 below $1 / GB.  That includes a 3 year warranty, quad core processor,
 4GB of RAM  which you can probably put to use elsewhere.
 
 
 
 
 
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Re: [CentOS] I need storage server advice

2008-05-06 Thread John R Pierce

Ross S. W. Walker wrote:


Take these benchmarks with a grain of salt.



and, more importantly, for the thread at hand, this guy wants an ARCHIVE 
server, where performance is quite secondary, reliablity and data 
retention are more important.


If he had the budget, I'd be suggesting looking at something like 
Copan's MAID system.



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Re: [CentOS] I need storage server advice

2008-05-06 Thread Jason Clark
The point was, acceptable performance can be had without purchasing a
hardware controller. And for archival purposes on a tight budget $500 bucks
means one controller for 3 more drives.

On Tue, May 6, 2008 at 6:17 PM, John R Pierce [EMAIL PROTECTED] wrote:

 Ross S. W. Walker wrote:

 
  Take these benchmarks with a grain of salt.
 
 
 and, more importantly, for the thread at hand, this guy wants an ARCHIVE
 server, where performance is quite secondary, reliablity and data retention
 are more important.

 If he had the budget, I'd be suggesting looking at something like Copan's
 MAID system.



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-- 
Jason
Luck favors the prepared.
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Re: [CentOS] I need storage server advice

2008-05-06 Thread Ross S. W. Walker

Yes, though slammed hardware RAID a bit. Software RAID has it's place don't
get me wrong, it's just knowing when and where.

Now the problem I have with your approach under the OP's
requirements is the only way to fit that kinda storage over that long a
period is with external enclosures and there isn't many systems that have 
external 4 lane serial storage
connectors builtin, so one needs a card that can perform that and if you are 
shopping for a card to do that
then you might as well get one for a few $100 more that has on board RAID. Also 
if the OP wanted to switch
distro's he will not have to worry about losing the RAID configuration or 
hosing it in the process.

-Ross


- Original Message -
From: [EMAIL PROTECTED] [EMAIL PROTECTED]
To: CentOS mailing list centos@centos.org
Sent: Tue May 06 20:39:52 2008
Subject: Re: [CentOS] I need storage server advice

The point was, acceptable performance can be had without purchasing a hardware 
controller. And for archival purposes on a tight budget $500 bucks means one 
controller for 3 more drives. 


On Tue, May 6, 2008 at 6:17 PM, John R Pierce [EMAIL PROTECTED] wrote:


Ross S. W. Walker wrote:



Take these benchmarks with a grain of salt.




and, more importantly, for the thread at hand, this guy wants an 
ARCHIVE server, where performance is quite secondary, reliablity and data 
retention are more important.

If he had the budget, I'd be suggesting looking at something like 
Copan's MAID system.



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-- 
Jason
Luck favors the prepared. 

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Re: [CentOS] I need storage server advice

2008-05-06 Thread John R Pierce

Ross S. W. Walker wrote:


Yes, though slammed hardware RAID a bit. Software RAID has it's place 
don't

get me wrong, it's just knowing when and where.

Now the problem I have with your approach under the OP's
requirements is the only way to fit that kinda storage over that long a
period is with external enclosures and there isn't many systems that 
have external 4 lane serial storage
connectors builtin, so one needs a card that can perform that and if 
you are shopping for a card to do that
then you might as well get one for a few $100 more that has on board 
RAID. Also if the OP wanted to switch
distro's he will not have to worry about losing the RAID configuration 
or hosing it in the process.




I've never had any problems with linux losing track of md based raid 
mirrors or LVM configurations, and they import quite nicely into new 
systems.



I'd consider using a SAS card on the host (LSI Logic makes some nice 
ones), and each SAS port can drive 16 SATA drives on SATA/SAS backplane 
multiplexors. 
http://www.lsi.com/storage_home/products_home/host_bus_adapters/sas_hbas/lsisas3801e/index.html


I'd start with a 3U 16 bay /server/ using a SAS/SATA backplane, too, 
then when that fills up, add 16 drive expansion bays as needed...
something like http://www.aicipc.com/ProductImage.aspx?ref=RSC-3ED2-2 
(but, by all means, pick your favorite chassis or system vendor)





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