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Cisco ISR4321/K9 4321 Integrated Services Router 2x Gigabit 50-100Mbps 2 NIM Slots - Refurbished

$329.00 USD

Ready to ship  -  1 left

Warranty: Lifetime

Condition: Refurbished

The Cisco ISR4321/K9 is a compact, high-performance Integrated Services Router from the Cisco 4000 Series, designed for small to medium branch offices and distributed enterprise sites. It provides secure, reliable WAN connectivity with built-in services like routing, security, voice, and application optimization, all while supporting modular expansion for flexibility.

Key Features and Specifications

  • Ports:
    • 2 × onboard Gigabit Ethernet (10/100/1000) ports (1 RJ-45, 1 SFP-based combo) configurable as WAN or LAN
    • 2 × Network Interface Module (NIM) slots for additional interfaces (e.g., T1/E1, serial, LTE, voice)
    • 1 × Internal Services Card (ISC) slot
  • Throughput:
    • Default (base) aggregate throughput: 50 Mbps
    • With performance license upgrade: Up to 100 Mbps
    • Supports Cisco Application Experience (AppX) for intelligent path selection and optimization
  • Software: Runs Cisco IOS XE (supports advanced routing protocols like BGP, OSPF, EIGRP; security features via licenses like Security, UC, etc.)
  • Memory: Default 4 GB DRAM and 4 GB Flash (expandable in some configurations)
  • Expansion: Modular design with NIM slots for OIR (Online Insertion/Removal) of modules
  • Power Supply: Internal AC power supply (redundant options available via external RPS in some setups)
  • Physical Dimensions: 1.75" H × 11.02" D × 12.7" W (1 RU rack-mountable)
  • Weight: Approximately 7.7 lb (3.5 kg)
  • Power Consumption: Around 40-90W depending on configuration and load
  • Environmental: Operating temperature 0°C to 40°C, fan-cooled
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  • 5 stars: 0 (0%)
  • 4 stars: 0 (0%)
  • 3 stars: 1 (100%)
  • 2 stars: 0 (0%)
  • 1 star: 0 (0%)
D
Daniel Moreau
Refurb unit needed a firmware update — cost us time we didn't have

We ordered this Cisco ISR4321/K9 refurbished router two days before a major client network audit and expected to rack it and move on. What we didn't account for — though in hindsight it's obvious — is that refurbished Cisco gear almost always needs a firmware upgrade before it matches your IOS-XE target. The unit itself is fine and worked after the update, but the update process added nearly three hours to our prep window. We were cutting it very close. I know this isn't really the seller's fault, but I was frustrated in the moment and the stars reflect that. The router itself performs exactly as expected for a branch office edge device.

Hi Daniel, thank you for sharing your honest experience. You're absolutely right that refurbished Cisco IOS-XE devices will often require a firmware update to reach your target version — it's a standard step we always recommend building into any deployment timeline. We completely understand the frustration when time is tight, especially before a client audit. We're glad the ISR4321 performed as expected once it was up to date. If it helps for future orders, our team is happy to advise on expected pre-deployment steps for any refurbished unit. Hope the audit went smoothly!