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Selection, compatibility, licensing, and EOL replacement guides for Cisco switches, routers, firewalls, wireless, and optics.
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How to Identify a Data Center Switch by PID, VID, and Serial Number and Order a Compatible Replacement
On a Cisco data center switch, the PID (Product ID) is the model, the VID (Version ID) is the hardware...
Rugged PoE Switch Selection Guide: Power Budget, Supply Sizing, and Uplinks on Cisco IE
A rugged PoE switch is sized from the devices it powers. Add up what each camera, access point, and sensor...
Data Center Switch Buying Guide: From Server Count to a Complete Cisco Nexus Order
Buying data center switches starts with the servers, not the switch catalog. Count the server ports and their speed, then...
Best Places to Buy Cisco Products Online: A Buyer’s Guide
Cisco hardware is sold online through independent stocking suppliers and Cisco’s authorized resellers. Cisco’s own web store, as of October...
Cisco Switch Lead Time: How Long Orders Take and Why It Varies
Cisco switch lead time is the time from order placement to product shipment, which is how Cisco’s own ordering documentation...
How to Check Cisco Switch Power Supply Status, Wattage, and Actual Power Use
On Catalyst 9200 and 9300 switches, start with show environment power all to see each power supply’s status and rated wattage. On...
Cisco MDS 9100 Port Licensing: What You Need to Add More Ports
A Cisco MDS 9100 port license increases the number of Fibre Channel ports authorized for use on the corresponding switch. To...
Cisco Switch Config Backup and Recovery on IOS XE
A Cisco switch configuration backup is only as good as the restore it supports. On a Catalyst 9000 switch running...
C9404R vs C9407R vs C9410R: Which Catalyst 9400 Chassis Should You Choose?
C9404R provides two line-card slots in 6 rack units, C9407R provides five in 10 rack units, and C9410R provides eight...
Cisco Catalyst 9400 Supervisor and Line Card Compatibility
C9400-LC-12QC, C9400-LC-24XY, C9400-LC-48HX, C9400-LC-48TX and C9400-LC-48XS require C9400X-SUP-2 or C9400X-SUP-2XL. The other nine line cards in the matrix below support all...
How to Check Cisco Warranty Status by Serial Number: 4 Ways
To check Cisco warranty status by serial number, start with the chassis serial number printed on the device label. Without...
Cisco StackWise Virtual Explained: Architecture, Forwarding, and Failure Recovery
Quick answer: Cisco StackWise Virtual combines two supported, directly connected switches into one logical system, with a shared control and management...
Catalyst 8000 vs Cisco 8000 Series Secure Routers: Why Catalyst Still Makes Sense
For a current purchase, start with Catalyst 8000 when its capacity, required features, support window, and confirmed delivery meet the...
Cisco Catalyst 9500 Architecture and Design Guide: UADP, Silicon One, SDM, and Deployment Choices
Quick answer: Three forwarding architectures share the Catalyst 9500 name. Earlier base C9500 models use the UADP 2.0 family, current high-performance...
How to Configure a Cisco IE1000: Express Setup and Device Manager Guide
Run Express Setup on a factory-default Cisco IE1000 to set its management address, management VLAN, gateway, time source, and a...
Cisco IOS XE Upgrade Guide for Switches and Routers
No single command sequence upgrades every IOS XE device safely. Establish the exact platform, current release, operating mode, boot mode,...
Cisco IOS vs IOS XE: Architecture, CLI, and Platform Differences
Classic Cisco IOS is the older, more tightly integrated network operating system used on many earlier Cisco routers and switches....
Cisco Nexus 9000 and 3000 NX-OS License Guide & Selector
Choose the switch’s license class first, then the feature tier, consumption model, term, and any add-ons. Essentials covers common routing,...
How to Configure a Cisco ASA Firewall: Step-by-Step CLI Guide
Quick answer: A working Cisco ASA baseline needs correctly addressed and enabled inside/outside interfaces, a default route, source PAT for the...
Fiber Optic Color Code Chart: TIA-598 for 12, 24, 48, and 144 Fibers
Quick answer: The TIA-598 color sequence is blue, orange, green, brown, slate, white, red, black, yellow, violet, rose, aqua. Those twelve...
Fiber Optic Connector Types: LC, SC, ST, FC, MPO, and MTP Explained
Quick answer: The main fiber optic connector types used in networks are LC, SC, ST, FC, MPO, and MTP. LC is...
Cisco Optics SKU Decoder: How to Read Common Ethernet Optics Part Numbers
Quick answer: Read most modern Cisco Ethernet optics product IDs (PIDs) from left to right: family → speed → media/reach → variant. SFP-10G-SR-S,...
Cisco MDS 9148T vs 9148V: Choosing Between 32G and 64G Fibre Channel
The Cisco MDS 9148T and MDS 9148V are both 48-port, 1RU fixed Fibre Channel switches in the MDS 9100 Series,...
Cisco Desk Phone 9800 Series Guide: 9811 vs 9841 vs 9851 vs 9861 vs 9871
The Cisco Desk Phone 9800 Series is Cisco’s current desk phone line: five models (9811, 9841, 9851, 9861, 9871) plus...
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