Your Storage Array Is Full. Again. You Have Three Choices.
Buy more drives, buy bigger drives, or buy a new storage server. The Seagate Exos X24 24TB makes option two dramatically more appealing than it was a year ago. At 24TB per 3.5-inch drive — double the capacity of the 12TB drives that were standard in 2020 — a single 12-bay server goes from 144TB raw to 288TB raw without adding a single drive slot, SAS expander, or power budget line item.
Six Questions Storage Architects Ask About 24TB Drives
1. Is this SMR or CMR? CMR (Conventional Magnetic Recording). The Exos X24 uses perpendicular magnetic recording with TDMR heads — no shingled write penalty. Random write performance is consistent, not burst-then-stall like SMR drives. For ZFS, Ceph, and any array that does not exclusively do sequential writes, CMR is non-negotiable.
2. What is the real rebuild time? At 270 MB/s sustained transfer, a full 24TB rebuild takes approximately 25 hours under ideal conditions. In a production array with concurrent workloads, plan for 30-36 ساعات. This is why RAID 6 or erasure coding (EC 8+2 أو 8+3) is strongly recommended over RAID 5 at this capacity — the probability of a second drive failure during a 36-hour rebuild window on 24TB drives is not negligible.
3. How does helium affect reliability? The Exos X24 is helium-sealed, which reduces internal turbulence and allows thinner platters. Lower drag means less motor power, less heat, and less vibration-induced wear. Seagate rates it at 2.5 million hours MTBF and 550 TB/year workload — enterprise-class numbers that match the 10K RPM SAS drives of a decade ago, at 7.2K RPM power draw.
4. 512e or 4Kn? Available in both. 4Kn (4K native) is preferred for modern file systems (ZFS, XFS, ReFS) and hypervisors (إسكسي 7.0+, Windows Server 2019+). 512e exists for legacy compatibility with older RAID controllers and operating systems. If you are building a new array, go 4Kn — the emulation layer in 512e adds latency on every I/O.
5. How does this compare to 20TB and 22TB? The last meaningful capacity jump was 20TB to 22TB — a 10% increase. The 22TB to 24TB jump is another 9%. At current street pricing, the cost-per-TB is nearly flat across 20TB, 22تيرابايت, and 24TB models. The real savings come from density: every 24TB drive you deploy instead of a 20TB drive saves one drive bay per 120TB of raw storage. In a 60-bay JBOD, that is 5 fewer drives, 5 fewer SAS ports, and roughly 40W less power.
6. What RAID/HBA controller do I need? Any LSI/Broadcom 93xx, 94xx, or 96xx series SAS HBA or RAID controller. PERC H740, ح750, H755, H965i are all compatible. The drive negotiates at 12Gb/s SAS — no special firmware or drivers required beyond the standard SAS controller driver for your OS.
المواصفات الفنية
| معامل | تخصيص |
|---|---|
| سعة | 24تيرابايت |
| عامل الشكل | 3.5-بوصة LFF |
| Interface | SAS 12 جيجابت / ثانية |
| سرعة الدوران | 7,200 RPM |
| Recording Technology | CMR (Conventional Magnetic Recording) with TDMR heads |
| Cache Buffer | 512MB |
| Sustained Transfer Rate | يصل إلى 270 ميغابايت/ق |
| Average Latency | 4.16 ms |
| MTBF | 2,500,000 ساعات |
| Workload Rate Limit | 550 TB/year |
| Unrecoverable Error Rate | 1 sector per 10^15 bits read |
| قوة (Idle / Operating) | 5.2دبليو / 8.3دبليو |
| Sealing | Helium-filled, hermetically sealed |
| Sector Size | 512e or 4Kn (selectable) |
| Physical Dimensions | 147.0 x 101.85 x 26.11 مم, 670g |
| درجة حرارة التشغيل | 5°C to 60°C |
| ضمان | 5-year limited (manufacturer) |
Compatible Platforms
Works with all Dell PowerEdge servers (R650, R660, R750, R760, R770, R860, R960), xFusion FusionServer V7 series, Lenovo ThinkSystem, and any SAS 12Gb/s backplane. Full compatibility with PERC H730/H740/H750/H755/H965i RAID controllers, LSI/Broadcom 93xx/94xx/96xx SAS HBAs, and all major SAS expander backplanes.
Who Should Not Buy the Exos X24
If you need IOPS, not capacity, this is the wrong drive. A 7.2K RPM HDD delivers roughly 150-180 random IOPS. For database volumes or virtualization, pair these with NVMe SSDs as a cache tier. If you need sub-2ms latency, look at SAS SSDs or NVMe drives. The Exos X24 is for bulk storage, backup repositories, media archives, and cold-to-warm data tiers — not for performance-critical primary storage.
Source Through Xincuan
We supply Seagate Exos enterprise drives in volume with factory-direct pricing, 3-year warranty, and global shipping. Volume discounts available for 20+ محركات. Our engineers can help plan your storage topology — from RAID groups to erasure coding schemes to tiered storage architectures.
