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I've have an ageing Linux server running on Dell PowerEdge hardware, with a SAS 5IR RAID controller. It has a pair of SAS 146Gb disks in a RAID 1 configuration that has the OS and other software. I have a need to add a large chunk of storage to the server. The data going on the disk isn't important, and with budget being limited for this, I've decided to add a large 2TB SATA disk to the unused SATA interface that is on board. The system sees the disk, but dmesg reports:

scsi 5:0:1:0: Direct-Access     ATA      WDC WD2002FAEX-0 05.0 PQ: 0 ANSI: 5
sd 5:0:1:0: [sdb] Very big device. Trying to use READ CAPACITY(16).
sd 5:0:1:0: [sdb] 18446744073321613488 512-byte hardware sectors (9444732965540666 MB)
sd 5:0:1:0: [sdb] Write Protect is off
sd 5:0:1:0: [sdb] Mode Sense: 00 3a 00 00
sd 5:0:1:0: [sdb] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA

As you can see above, the size is reported incorrectly. I suspect it might be a limitation of the kernel I'm running, but I can't find anything to support this theory. Can anybody confirm if this is likely to be the case?

The OS is Ubuntu 7.10 (Server, x64 IIRC, no GUI), running kernel 2.6.22-14-server.

BTW: Yes, I know it's a non LTS version of Ubuntu, and it is very out of date. This isn't a security risk in the scenario it is being used in. I'm hoping to not have to update the kernel or OS if it can be avoided, but am prepared to do so, if I'm sure it will resolve the problem.

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Upgrade Ubuntu? – kinokijuf Jan 13 '12 at 16:07
Are you sure the SATA controller can handle disks of that size? Maybe a firmware update is needed. – SpacemanSpiff Jan 13 '12 at 16:08
@SpacemanSpiff Good point, I hadn't thought of that, and will investigate. – Bryan Jan 13 '12 at 16:17
@kinokijuf As per my question, I'm happy to upgrade if it will solve the problem, but the upgrade isn't a trivial job for all sorts of reasons, and I don't want to waste time if I can avoid it. – Bryan Jan 13 '12 at 16:18
@SpacemanSpiff, looks like you've identified the problem. The SATA controller on board supports 4 x 1TB disks. There are firmware upgrades available for the server, but unhelpfully, Dell don't offer any release notes to go with them, but I'll upgrade to the latest revision and see if it helps. - BTW, if you post your comment as an answer, I'll accept your solution. Thanks. – Bryan Jan 13 '12 at 16:30
up vote 4 down vote accepted

Take a look at the firmware releases for the SATA controller, it may not support drives of that size. It could be part of the mainboard or baseboard updates as well.

Consider putting the disk in an enclosure and connecting via USB2.0 as a workaround. If you don't have 2.0 ports, use a PCI USB 2.0 card to expand.

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