IBM 49Y1880 300GB SAS 10K HDD: Boot Mirror and Array Guide
Every server needs somewhere to put its operating system, and that volume has requirements almost opposite to everything else in the chassis. It needs to be reliable and it needs to be boring. Capacity and speed barely matter.
The IBM 49Y1880 is a 300GB SAS 6Gb/s 10K 2.5-inch hot-swap drive, and boot mirrors are one of the most common things it is bought for.
Why boot volumes get their own drives
Running the operating system on the same array as the data seems efficient and creates a problem that only shows up when things go wrong.
Rebuilds affect everything. When a data array rebuilds, it is under sustained load for hours. If the OS lives there too, the server itself becomes sluggish exactly when you are trying to work on it.
Recovery gets complicated. Rebuilding a server is far simpler when the OS volume is separate. You can rebuild, reconfigure or replace the data array without touching the boot volume, and vice versa.
Different requirements. A data array is sized for capacity or IOPS. A boot volume needs neither — it needs to survive a single drive failure without interrupting the server, which is a job for a simple two-drive mirror.
That is why a pair of modest drives in RAID 1 is the standard pattern. Two 300GB drives is generous for an operating system, its logs and its swap, and mirroring means either one can fail without the server stopping.
49Y1880 specifications
| Part Number | 49Y1880 |
| Manufacturer | IBM |
| Capacity | 300GB |
| Interface | SAS 6Gb/s |
| Rotational Speed | 10,000 RPM |
| Form Factor | 2.5 inch SFF |
| Carrier Type | Hot-Swap |
| Drive Class | Enterprise Performance |
| Condition | Refurbished, function-tested |
| Warranty | 30-day TechSellerUSA warranty |
Buy boot drives in pairs
A practical point that is easy to get wrong when replacing a failed mirror member.
If one drive of a RAID 1 pair has failed after years of service, the surviving drive has exactly the same accumulated hours, the same manufacturing batch and the same operating conditions. It is not a fresh drive; it is the other half of a pair that has started failing.
Replacing only the failed one restores redundancy, and it leaves you with a mirror where one member is statistically overdue. Many sites replace both, retiring the survivor to a spares shelf or to a non-critical role.
At minimum, if you replace one, hold a spare for the other. Boot mirror failures are among the most disruptive because the server stops rather than slowing down, and on IBM System x there is no straightforward parts channel since the business moved to Lenovo.
SKU: 49Y1880 | Refurbished & function-tested | Hot-swap carrier | 30-day warranty
View Details & Request a Quote →Also a general-purpose array drive
Boot mirrors are one use; the other is ordinary array population, and 10K at 300GB is a sensible tier for it.
10K sits between the 15K performance tier and 7200 RPM nearline, and it is the answer when the workload is mixed — which describes most servers. A virtualisation host runs some busy VMs and some idle ones. An application server has hot tables and cold logs. For those, 10K delivers enough IOPS that storage is not the bottleneck without the capacity penalty and heat of 15K.
At 300GB specifically, you are getting spindle count rather than capacity, which suits arrays where concurrency matters more than terabytes. Where you need more capacity per bay at the same speed, 600GB and larger 10K drives fit the same bays.
Carrier and firmware on IBM System x
This drive ships in an IBM hot-swap carrier, meaning the chassis has hot-swap bays with a lever on each tray. The alternative is simple-swap, which requires the server powered down and has no lever. Later systems used G2HS and then G3HS generations. None of the four interchange.
IBM also codes drive firmware and ServeRAID controllers check it. A generic drive may work while flagged unsupported, may not report health telemetry so predictive warnings never arrive, or may be refused during a rebuild.
On a boot mirror the firmware point is worth taking seriously, because a rejected drive means the mirror stays degraded and the server is running on a single drive with no redundancy at all.
Ordering
We supply the 49Y1880 refurbished and function-tested with a 30-day warranty. Boot mirrors are usually bought in pairs, so tell us how many servers you are covering. Browse the full IBM range, our complete enterprise hard drives catalogue, or the compatibility guide for carrier requirements by platform.
Common questions
Why put the operating system on separate drives?
Because a data array rebuild puts the whole array under sustained load for hours, and if the OS lives there the server becomes sluggish exactly when you need to work on it. Separation also makes rebuilding or replacing either volume far simpler.
Should I replace both drives in a failed boot mirror?
Often worth it. The surviving drive has the same accumulated hours, batch and operating conditions as the one that just failed, so it is statistically overdue. At minimum, replace one and hold a spare for the other.
Is 300GB enough for a boot volume?
Generous for an operating system, its logs and swap. Boot volumes need reliability rather than capacity, which is why a pair of modest drives in RAID 1 is the standard pattern rather than something larger.
Does firmware coding matter on a boot mirror?
More than usual. If a ServeRAID controller refuses a generic drive, the mirror stays degraded and the server runs on a single drive with no redundancy at all. Order by IBM part number for boot volumes.
Tell us how many servers need boot mirrors and we will quote in pairs with spares.
