Answer-first buying guides
Written by the network engineers who test the hardware. Straight answers on condition tiers, used-server safety, transceiver compatibility and server memory — specs and part numbers first, no hype.
Before you commit a PO
Vetting sellers, warranties and data handling before a purchase order goes out.
Spending the budget well
Condition tiers, warranty entitlement, capacity and cost — how to choose the right SKU.
Refurbished vs new vs recertified
The three condition tiers, the warranty each actually carries, and where the 60–90%-below-new savings sit.
Read guide → BuyingRDIMM vs LRDIMM
Registered vs load-reduced server memory: buffering, rank, capacity and latency compared — and which to populate.
Read guide →From the switch-port side of the rack
Switches, optics, coding and compatibility — the engineering detail that decides whether a link comes up.
Refurbished network switches: the complete buying guide
Family, condition grade, Cisco license tier, PoE budget and support life — the five things that decide whether a used switch drops into your rack cleanly.
Read guide → CompatibilityWhich SFP works with a Catalyst 9300?
The network-module-to-optic matrix: which SFP, SFP+, mGig and QSFP each C9300 uplink module accepts, plus coded-optic guidance.
Read guide → NetworkingSFP & SFP+ transceiver compatibility
Coding, vendor lock and DOM — and how to run third-party optics in Cisco, Arista and Juniper.
Read guide → ReferenceSFP vs SFP+ vs SFP28 vs QSFP
The form-factor ladder from 1G to 100G: speeds, backward compatibility and breakout options in one table.
Read reference → How-toFactory reset a Cisco switch
write erase, delete vlan.dat and reload — plus the Catalyst 9000 factory-reset command and Mode-button recovery.
Read guide → BuyingUsed firewalls: licenses & subscriptions
What transfers and what doesn't — FortiGate, Palo Alto, Cisco and SonicWall rules, and what works without a subscription.
Read guide →Day-one on a used server
The out-of-band tasks every refurbished-server buyer hits first — resetting and getting into iDRAC.
How to reset iDRAC
Three methods — racadm over SSH, F2 iDRAC Settings at boot, and the web GUI — plus the 16-second System ID reset.
Read guide → ReferenceiDRAC default password
root / calvin on iDRAC 7/8, or a unique per-unit password on 14th-gen PowerEdge and newer — with the full reference table.
Read reference → How-toHow to reset HPE iLO
Web GUI, SSH reset /map1, hponcfg from the host OS, and the Security Override path — plus the default Administrator password.
Read guide →Comparisons & end-of-life
Model-versus-model breakdowns and verified end-of-support dates with the refurbished replacement path.
Cisco Catalyst 9300 vs 9200
StackWise bandwidth, uplink modularity, ASIC tier, PoE and licensing — and which fits access vs aggregation.
Compare → End-of-lifeCisco Catalyst 3850 end of life
End-of-sale and last-date-of-support milestones, plus the WS-C3850 → Catalyst 9300 migration mapping.
Read →Know the part, need the match?
Enter a server or switch model — or an OEM part number — and the Compatibility Tool returns the drives, DIMMs, PSUs and transceivers we stock for it, with firmware and spec detail.