Comments on: Disk in … disk out … http://storageadvisors.adaptec.com/2008/11/05/disk-in-%e2%80%a6-disk-out-%e2%80%a6/ Storage Solutions for Real World IT Professionals Wed, 17 Mar 2010 03:57:16 +0000 http://wordpress.org/?v=1.5.2 Comment on Disk in … disk out … by: Neil http://storageadvisors.adaptec.com/2008/11/05/disk-in-%e2%80%a6-disk-out-%e2%80%a6/#comment-323080 Tue, 03 Mar 2009 11:32:58 +0000 http://storageadvisors.adaptec.com/2008/11/05/disk-in-%e2%80%a6-disk-out-%e2%80%a6/#comment-323080 Rob, Great questions ... and it indicates that I didn't make things real clear in the first place :-) So ... I'll do this point by point ... Yes, it's possible to do RAID arrays on an external JBOD - using the RAID card in the server attached by the 4x external SAS connector on both the RAID card and the JBOD. 10tb is not a problem ... we go up to 512tb in a single RAID array. Don't buy a SAS RAID enclosure, buy a SAS JBOD enclosure. Connect to the external port on the RAID card. Since you mentioned a 1U server then the 5445 is perfect. 4 internal ports for the drives in the server, and an external connector to go to the JBOD. SMB/CIFS no worries ... you'll probably want to use SATA (something like Seagate ES2 - watch the firmware). (iSCSI? Please explain. I need clarification on exactly what you mean here, what servers you have, what storage you need, how good your network is and where you want to store the data in relation to the processing. In other words ... put this as a separate question so we don't muddy the water.) So ... Question 1: Yes Question 2: Yes ... the connection supports 1200mb/second which is fast enough for good old CIFS. As for dual ports etc, that's a good topic for another blog (I'll put it in my section on things to write about on the way home in the train :-)) Thanks Neil Rob,

Great questions … and it indicates that I didn’t make things real clear in the first place :-)

So … I’ll do this point by point …

Yes, it’s possible to do RAID arrays on an external JBOD - using the RAID card in the server attached by the 4x external SAS connector on both the RAID card and the JBOD.

10tb is not a problem … we go up to 512tb in a single RAID array.

Don’t buy a SAS RAID enclosure, buy a SAS JBOD enclosure. Connect to the external port on the RAID card. Since you mentioned a 1U server then the 5445 is perfect. 4 internal ports for the drives in the server, and an external connector to go to the JBOD.

SMB/CIFS no worries … you’ll probably want to use SATA (something like Seagate ES2 - watch the firmware).

(iSCSI? Please explain. I need clarification on exactly what you mean here, what servers you have, what storage you need, how good your network is and where you want to store the data in relation to the processing. In other words … put this as a separate question so we don’t muddy the water.)

So …

Question 1: Yes
Question 2: Yes … the connection supports 1200mb/second which is fast enough for good old CIFS.

As for dual ports etc, that’s a good topic for another blog (I’ll put it in my section on things to write about on the way home in the train :-) )

Thanks
Neil

]]> Comment on Disk in … disk out … by: Rob http://storageadvisors.adaptec.com/2008/11/05/disk-in-%e2%80%a6-disk-out-%e2%80%a6/#comment-322643 Mon, 02 Mar 2009 03:15:41 +0000 http://storageadvisors.adaptec.com/2008/11/05/disk-in-%e2%80%a6-disk-out-%e2%80%a6/#comment-322643 Hi, Your coment above implies that it's possible to configure RAID arrays on JOBD external enclosures? As per your suggtestion I'm wanting to set up a storage system with at least 10TB using a 12 disk SAS external enclosure attached to a 1U server. I havent had much to do with SAS, and was going to purchase an external array enclosure that specifies itself as a SAS RAID enclosure. Is it necessary to purchase a RAID enclosure, or can I configure RAID on a JBOD array enclosure using an adaptec HBA with external 4x SAS connector? The system will be used for SMB/CIFS network file serving (either by server 2003 or open filer or similiar), and if expandable we might add a second external enclosure with higher speed disk to service database and exchange servers via iscsi. I guess my questions are; 1. Can external disk arrays that are sold as JBOD (not RAID) be used to set up RAID disk arrays via the Adaptec HBA in the server? 2. Is there enough bandwidth on a single 4x external SAS port to serve 2 external disk arrays via daisy chaining - or would i use a HBA with 2 or more external ports? Thanks. Hi,

Your coment above implies that it’s possible to configure RAID arrays on JOBD external enclosures?

As per your suggtestion I’m wanting to set up a storage system with at least 10TB using a 12 disk SAS external enclosure attached to a 1U server.

I havent had much to do with SAS, and was going to purchase an external array enclosure that specifies itself as a SAS RAID enclosure. Is it necessary to purchase a RAID enclosure, or can I configure RAID on a JBOD array enclosure using an adaptec HBA with external 4x SAS connector?

The system will be used for SMB/CIFS network file serving (either by server 2003 or open filer or similiar), and if expandable we might add a second external enclosure with higher speed disk to service database and exchange servers via iscsi.

I guess my questions are;

1. Can external disk arrays that are sold as JBOD (not RAID) be used to set up RAID disk arrays via the Adaptec HBA in the server?

2. Is there enough bandwidth on a single 4x external SAS port to serve 2 external disk arrays via daisy chaining - or would i use a HBA with 2 or more external ports?

Thanks.

]]> Comment on Disk in … disk out … by: Neil http://storageadvisors.adaptec.com/2008/11/05/disk-in-%e2%80%a6-disk-out-%e2%80%a6/#comment-296542 Wed, 21 Jan 2009 02:27:23 +0000 http://storageadvisors.adaptec.com/2008/11/05/disk-in-%e2%80%a6-disk-out-%e2%80%a6/#comment-296542 Paul, FUD goes well with Coffee. So ... the drives in the JBOD would be in a RAID array controlled by the card. Upon re-reading my ramble I realise I didn't make this particularly clear (for which I apologise). If the drives are in a RAID array of some description (probably 5, 6, 50 or 60) then of course we can survive the drive failure. If you have a hot spare lying around the place then of course the array will rebuild straight away and you're safe once more. Even in the bizarre situation where you did in fact have single drives in a JBOD, the failure of one drive would only affect access to that drive, not the rest of the drives in the JBOD. Remember that SAS/SATA is point to point, not a parallel technology like the old SCSI so single device failures don't affect devices around them. Hope that answers the question. Thanks Neil Paul,

FUD goes well with Coffee.

So … the drives in the JBOD would be in a RAID array controlled by the card. Upon re-reading my ramble I realise I didn’t make this particularly clear (for which I apologise).

If the drives are in a RAID array of some description (probably 5, 6, 50 or 60) then of course we can survive the drive failure. If you have a hot spare lying around the place then of course the array will rebuild straight away and you’re safe once more.

Even in the bizarre situation where you did in fact have single drives in a JBOD, the failure of one drive would only affect access to that drive, not the rest of the drives in the JBOD. Remember that SAS/SATA is point to point, not a parallel technology like the old SCSI so single device failures don’t affect devices around them.

Hope that answers the question.

Thanks
Neil

]]> Comment on Disk in … disk out … by: Paul http://storageadvisors.adaptec.com/2008/11/05/disk-in-%e2%80%a6-disk-out-%e2%80%a6/#comment-293697 Fri, 16 Jan 2009 19:32:52 +0000 http://storageadvisors.adaptec.com/2008/11/05/disk-in-%e2%80%a6-disk-out-%e2%80%a6/#comment-293697 Here's some FUD on my part, but: What happens if one of the drives in the JBOD fails? Do you lose access to the data until you can restore from backup? Or can you RAID the JBOD drives for redundancy? Here’s some FUD on my part, but:

What happens if one of the drives in the JBOD fails? Do you lose access to the data until you can restore from backup? Or can you RAID the JBOD drives for redundancy?

]]> Comment on Disk in … disk out … by: Neil http://storageadvisors.adaptec.com/2008/11/05/disk-in-%e2%80%a6-disk-out-%e2%80%a6/#comment-276045 Sun, 21 Dec 2008 15:06:42 +0000 http://storageadvisors.adaptec.com/2008/11/05/disk-in-%e2%80%a6-disk-out-%e2%80%a6/#comment-276045 Kman, Once upon a time, in a galaxy far, far away ... yes, there was a limit of 48 sata drives on the 4800/4805 series of adpaters. Not so for the 5 series of Adpatec RAID cards. 256 is definitely the limit for either SAS and/or SATA drives. Now as for chassis ... you'll generally only find 12-24 bay chassis out there, but you can daisy-chain them very easily (in fact it's piece of cake) to give you the expansion capacity you need. Thanks Neil Kman,

Once upon a time, in a galaxy far, far away … yes, there was a limit of 48 sata drives on the 4800/4805 series of adpaters. Not so for the 5 series of Adpatec RAID cards. 256 is definitely the limit for either SAS and/or SATA drives.

Now as for chassis … you’ll generally only find 12-24 bay chassis out there, but you can daisy-chain them very easily (in fact it’s piece of cake) to give you the expansion capacity you need.

Thanks
Neil

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