DatacenterDisk
HP

695510-B21 4TB SAS 6G

695510-B21
ProLiant OEMnearlineCMR4TBSAS-6G3.5"
$13.75/TB
$55.00
newIn Stock
Updated Mar 25, 2026, 05:51 AM
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Quick Verdict

The HP 695510-B21 4TB SAS 6G is a 4TB SAS-6G enterprise drive at $13.75/TB - CMR recording makes it safe for all RAID levels and NAS deployments. New unit with full manufacturer warranty.

Specifications

Capacity4TB
Form Factor3.5"
InterfaceSAS-6G
Recording TechCMR
RPM7200
Cache—
Sector Size512n
Workload Rating—
Warranty—
ASINB07XB3B7QB

90-Day Price History

$13$14$1503/2304/2906/05
How it compares - 4TB SAS-6G
#1HP 695510-B21 4TB SAS 6GTHIS DRIVE
$13.75/TB
#2HP 695510-B21 4TB SAS 6GTHIS DRIVE
$13.75/TB
#3HP 695842-001 4TB SAS 6G
$14.00/TB
#4HP 695842-001 4TB SAS 6G
$14.00/TB
#5Dell DRMYH Compellent 4TB NL SAS Renewed
$14.10/TB

Compare to similar 4TB SAS-6G drives

HP
695842-001 4TB SAS 6G
$14.00/TB
$55.99
new
HP
695842-001 4TB SAS 6G
$14.00/TB
$55.99
REFURB
Dell
DRMYH Compellent 4TB NL SAS Renewed
$14.10/TB
$56.39
new
Dell
DRMYH Compellent 4TB NL SAS Renewed
$14.10/TB
$56.39
REFURB
Dell
529FG 4TB SAS 6G Renewed
$15.00/TB
$60.00
REFURB

Frequently Asked Questions

Yes. The 695510-B21 4TB SAS 6G uses CMR recording which is fully compatible with all RAID levels.

Warranty varies by seller. Check the Amazon listing for current warranty terms.

Compatible with any server or workstation equipped with a SAS HBA or SAS backplane. Tested with Dell PowerEdge, HPE ProLiant, Supermicro and IBM System x platforms.

Use Case Scenarios

🏠
Home & SMB NAS
Building a mid-range NAS for media, backups and file sharing.
✓ Excellent fit
CMR recording is RAID-safe and fully compatible with Synology, QNAP, TrueNAS and UnRAID. New drives come with full warranty.
💾
Backup Server / Veeam Target
Dedicated backup storage for Veeam, Commvault, or NetBackup.
✓ Excellent fit
4TB SAS drives are ideal for backup targets. Dual-port SAS suits dual-path backup infrastructure.
🏗️
Virtualization Host Storage
VM images and snapshots on Proxmox, VMware or Hyper-V.
~ Good fit
Suitable for VM storage where workloads are not IOPS-intensive. SAS dual-port suits HA cluster shared storage. Consider NVMe cache for latency-sensitive VMs.

Maintenance & Troubleshooting

Maintenance Checklist

On installCheck SMART baseline on arrival
Run smartctl -a /dev/sdX and record: Reallocated_Sector_Ct, Power_On_Hours, Spin_Retry_Count. Establishes baseline for future comparison.
MonthlyRun SMART short self-test
smartctl -t short /dev/sdX — takes 1-2 minutes, catches most developing issues. Schedule during off-peak.
QuarterlyRun SMART long self-test
smartctl -t long /dev/sdX — full surface scan, takes 2 hours for 4TB. Any test failure is grounds for immediate replacement.
QuarterlyCheck RAID array health
Verify no degraded drives. A degraded array with no hot spare is one failure from data loss. Check mdstat or controller UI.
AnnuallyVerify drive firmware version
Check HP support site for firmware updates. Some versions have known bugs affecting integrity.
Every 3-5 yearsPlan proactive replacement
Enterprise HDDs have higher failure rates after year 4-5. At 4TB per drive, budget for replacements before failures occur.

Troubleshooting Guide

Cause: HBA not initialized, SAS expander issue, cable fault, or incompatible controller.
Fix: Verify HBA firmware. Check SAS topology with sas2ircu or StorCLI. Test with known-good cable. Confirm drive is SAS not SATA.