<\/span><\/h3>\nHow many switches can participate in a single Cisco Catalyst 9300 stack?<\/h4>\n
Across all models within the Cisco Catalyst 9300 family\u2014including Catalyst 9300, 9300X, 9300L, and 9300LM\u2014the maximum supported stack size is 8 switches<\/strong>. When 8 switches are stacked using a closed-ring topology, they operate under a single management IP address and present up to 448 access ports as one logical switch.<\/p>\nWhat is the maximum stacking bandwidth available for Cisco 9300 switches?<\/h4>\n
Stacking bandwidth depends on the specific hardware tier and stacking architecture:
\n* StackWise-1T (Catalyst 9300X models):<\/strong> Provides up to 1 Tbps<\/strong> (1000 Gbps) of bidirectional stack bandwidth when all members are 9300X switches.
\n* StackWise-480 (Standard modular Catalyst 9300 models):<\/strong> Delivers 480 Gbps<\/strong> of bidirectional stack bandwidth.
\n* StackWise-320 (Catalyst 9300L and 9300LM fixed-uplink models):<\/strong> Delivers 320 Gbps<\/strong> of bidirectional stack bandwidth.<\/p>\nHow does StackWise handle switch roles across the 8 members?<\/h4>\n
The stack automatically establishes three primary roles:
\n1. Active Switch:<\/strong> Manages the entire stack, executes Layer 2 and Layer 3 control planes, runs management protocols, and handles system configuration.
\n2. Standby Switch:<\/strong> Synchronizes running configuration and protocol states with the Active switch via Nonstop Forwarding (NSF) and Stateful Switchover (SSO), maintaining sub-50 ms failover readiness.
\n3. Member Switches:<\/strong> Act as line cards within the unified system, handling local packet switching and distributed data forwarding.<\/p>\nDoes Cisco StackPower also support up to 8 switches?<\/h4>\n
No. StackWise (data stacking) and StackPower (power stacking) operate under different scalability rules. While data stacking supports up to 8 switches, Cisco StackPower supports a maximum of 4 switches in a single power-stack ring<\/strong> (or up to 8 switches when configured in a star topology with an external power expansion system). StackPower is supported exclusively on modular Catalyst 9300 and 9300X models; fixed-uplink 9300L and 9300LM models do not support StackPower.<\/p>\n
\n<\/span>Mixed Stacking Compatibility: 9300 vs. 9300L vs. 9300X<\/span><\/h2>\nNot every Catalyst 9300 model can be physically interconnected. Cisco maintains architectural separation between modular-uplink models and fixed-uplink models due to distinct internal backplane ASICs and connector hardware. <\/p>\n
The following comparison table details the stacking support rules across the Catalyst 9300 product lines:<\/p>\n
\n\n\n| Feature \/ Compatibility Criteria<\/th>\n | Catalyst 9300 (Modular)<\/th>\n | Catalyst 9300X (Modular 1T)<\/th>\n | Catalyst 9300L (Fixed Uplink)<\/th>\n | Catalyst 9300LM (Mini Fixed)<\/th>\n | Catalyst 3850 \/ Older Legacy<\/th>\n<\/tr>\n<\/thead>\n |
\n\nStacking Architecture<\/strong><\/td>\n| StackWise-480<\/td>\n | StackWise-1T<\/td>\n | StackWise-320<\/td>\n | StackWise-320<\/td>\n | StackWise-480 \/ StackWise-Plus<\/td>\n<\/tr>\n | \nMax Stack Members<\/strong><\/td>\n| 8<\/td>\n | 8<\/td>\n | 8<\/td>\n | 8<\/td>\n | 9 (Catalyst 3850)<\/td>\n<\/tr>\n | \nCan Stack With Standard 9300?<\/strong><\/td>\n| Yes (Native 480 Gbps)<\/td>\n | Yes (Throttled to 480 Gbps)<\/td>\n | No<\/strong> (Incompatible)<\/td>\nNo<\/strong> (Incompatible)<\/td>\nNo<\/strong> (Incompatible)<\/td>\n<\/tr>\n\nCan Stack With 9300X?<\/strong><\/td>\n| Yes (Operates at 480 Gbps)<\/td>\n | Yes (Full 1 Tbps)<\/td>\n | No<\/strong> (Incompatible)<\/td>\nNo<\/strong> (Incompatible)<\/td>\nNo<\/strong> (Incompatible)<\/td>\n<\/tr>\n\nCan Stack With 9300L?<\/strong><\/td>\nNo<\/strong> (Incompatible)<\/td>\nNo<\/strong> (Incompatible)<\/td>\n| Yes (Full 320 Gbps)<\/td>\n | Yes (Requires STACK-KIT2)<\/td>\n | No<\/strong> (Incompatible)<\/td>\n<\/tr>\n\nCan Stack With 9300LM?<\/strong><\/td>\nNo<\/strong> (Incompatible)<\/td>\nNo<\/strong> (Incompatible)<\/td>\n| Yes (Requires STACK-KIT2)<\/td>\n | Yes (Full 320 Gbps)<\/td>\n | No<\/strong> (Incompatible)<\/td>\n<\/tr>\n\nStackPower Support<\/strong><\/td>\n| Yes (Up to 4 switches)<\/td>\n | Yes (Up to 4 switches)<\/td>\n | No<\/strong><\/td>\nNo<\/strong><\/td>\n| Yes (3850 only)<\/td>\n<\/tr>\n | \nCable \/ Adapter Type<\/strong><\/td>\n| STACK-T1 Cables<\/td>\n | STACK-T1 Cables<\/td>\n | C9300L-STACK-KIT \/ KIT2<\/td>\n | C9300L-STACK-KIT2<\/td>\n | Incompatible connectors<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/span>Critical Architectural Constraints<\/span><\/h3>\n\n- 9300 with 9300X Mixed Stacks:<\/strong> You can mix standard Catalyst 9300 and 9300X switches in the same physical stack. However, the entire ring downshifts to the lowest common denominator: StackWise-480 (480 Gbps). The 1 Tbps rate is only engaged when every member switch in the ring is a 9300X model.<\/li>\n
- Modular vs. Fixed Uplink Separation:<\/strong> Under no circumstances can fixed-uplink models (9300L\/9300LM) be stacked with modular switches (9300\/9300X). They use physically and electrically incompatible stack ports and adapter kits.<\/li>\n
- High-Scale Model Restrictions:<\/strong> Specific high-performance SKUs (e.g., C9300-24UB, C9300-24UXB, and C9300-48UB) cannot be mixed with standard C9300 SKUs and must be stacked strictly with identical high-scale models.<\/li>\n
- License Consistency:<\/strong> All stack members must run identical software tiers (Network Essentials or Network Advantage). A stack member configured with Network Essentials cannot join an active stack running Network Advantage.<\/li>\n<\/ul>\n
\n<\/span>Cisco Catalyst 9300 Stacking Cables and Hardware Kits<\/span><\/h2>\nEstablishing a reliable StackWise ring requires specific cables and slot adapters matching the physical switch model. The table below lists the current part numbers, lengths, and hardware compatibility specifications.<\/p>\n \n\n\n| Part Number (PID)<\/th>\n | Component Description<\/th>\n | Hardware Compatibility<\/th>\n | Cable Length<\/th>\n | Data \/ Stacking Throughput<\/th>\n<\/tr>\n<\/thead>\n | \n\nSTACK-T1-50CM<\/strong><\/td>\n| Cisco StackWise-480\/1T Data Cable<\/td>\n | Catalyst 9300, Catalyst 9300X<\/td>\n | 0.5 meter (50 cm)<\/td>\n | Up to 1 Tbps (Bidirectional)<\/td>\n<\/tr>\n | \nSTACK-T1-1M<\/strong><\/td>\n| Cisco StackWise-480\/1T Data Cable<\/td>\n | Catalyst 9300, Catalyst 9300X<\/td>\n | 1.0 meter (100 cm)<\/td>\n | Up to 1 Tbps (Bidirectional)<\/td>\n<\/tr>\n | \nSTACK-T1-3M<\/strong><\/td>\n| Cisco StackWise-480\/1T Data Cable<\/td>\n | Catalyst 9300, Catalyst 9300X<\/td>\n | 3.0 meters (300 cm)<\/td>\n | Up to 1 Tbps (Bidirectional)<\/td>\n<\/tr>\n | \nC9300L-STACK-KIT<\/strong><\/td>\n| StackWise-320 Kit (2 Adapters + STACK-T3 Cable)<\/td>\n | Catalyst 9300L only (Legacy \/ End-of-Sale)<\/td>\n | 0.5 meter included<\/td>\n | 320 Gbps (Bidirectional)<\/td>\n<\/tr>\n | \nC9300L-STACK-KIT2<\/strong><\/td>\n| StackWise-320 Kit (2 Adapters + STACK-T3A Cable)<\/td>\n | Catalyst 9300L and Catalyst 9300LM<\/td>\n | 0.5 meter included<\/td>\n | 320 Gbps (Bidirectional)<\/td>\n<\/tr>\n | \nSTACK-T3-50CM \/ 1M \/ 3M<\/strong><\/td>\n| Spare Type-3 Stacking Cable<\/td>\n | C9300L-STACK Adapter<\/td>\n | 0.5 m, 1.0 m, 3.0 m<\/td>\n | 320 Gbps (Bidirectional)<\/td>\n<\/tr>\n | \nSTACK-T3A-50CM \/ 1M \/ 3M<\/strong><\/td>\n| Spare Type-3A Stacking Cable<\/td>\n | C9300L-STACK-A (KIT2) Adapter<\/td>\n | 0.5 m, 1.0 m, 3.0 m<\/td>\n | 320 Gbps (Bidirectional)<\/td>\n<\/tr>\n | \nCAB-SPWR-30CM<\/strong><\/td>\n| Cisco StackPower Cable<\/td>\n | Catalyst 9300, Catalyst 9300X only<\/td>\n | 30 cm<\/td>\n | Redundant \/ Shared DC Power<\/td>\n<\/tr>\n | \nCAB-SPWR-150CM<\/strong><\/td>\n| Cisco StackPower Cable<\/td>\n | Catalyst 9300, Catalyst 9300X only<\/td>\n | 150 cm<\/td>\n | Redundant \/ Shared DC Power<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n Note: STACK-T3 and STACK-T3A cables use different keying mechanisms and cannot be interchanged on the same adapter. If deploying Catalyst 9300LM switches or expanding older 9300L stacks, ensure C9300L-STACK-KIT2 hardware is utilized throughout the new links.<\/em><\/p>\n
\n<\/span>Step-by-Step Guide: Cabling and Configuring a Cisco 9300 Stack<\/span><\/h2>\nSetting up a Catalyst 9300 stack requires careful execution of physical ring cabling, deterministic switch priority settings, and coordinated power cycling to ensure the intended switch assumes the Active role.<\/p>\n <\/span>Step 1: Pre-Stack Verification and Image Alignment<\/span><\/h3>\nBefore installing the switches in a rack:
\n1. Power on each switch independently.
\n2. Confirm that each unit runs the identical Cisco IOS-XE release:
\n text
\n Switch# show version<\/code>
\n3. Verify that all switches share the same licensing package (e.g., Network Advantage vs. Network Essentials):
\n text
\n Switch# show license summary<\/code>
\n4. Power off all switches completely once confirmed.<\/p>\n<\/span>Step 2: Physical Cabling in a Closed-Ring Topology<\/span><\/h3>\nTo achieve full stacking bandwidth and fault tolerance, cable the switches in a redundant closed-ring topology. Each switch has two stack ports (Port 1 and Port 2) on the rear chassis:<\/p>\n Switch 1 (Top) [Port 1] -----------\\\n [Port 2] -------\\ |\n | |\n Switch 2 (Middle) [Port 1] <------\/ |\n [Port 2] -------\\ |\n | |\n Switch 3 (Bottom) [Port 1] <------\/ |\n [Port 2] -----------\/ (Closes the Ring)\n<\/code><\/pre>\n\n- Connect a StackWise cable from Switch 1, Port 2<\/strong> down to Switch 2, Port 1<\/strong>.<\/li>\n
- Connect from Switch 2, Port 2<\/strong> down to Switch 3, Port 1<\/strong>.<\/li>\n
- Complete the ring by connecting the remaining bottom port (Switch 3, Port 2<\/strong>) back to the top port (Switch 1, Port 1<\/strong>).
\nIf any single cable fails, the stack automatically fails over to a half-ring topology without interrupting traffic forwarding.<\/em><\/li>\n<\/ol>\n<\/span>Step 3: Setting Switch Priorities and Member Numbers<\/span><\/h3>\nPriority values range from 1 to 15<\/strong>, where 15 is the highest priority<\/strong> (default is 1). The switch with the highest priority wins the election to become the Active switch.<\/p>\n\n- Power on only<\/strong> the designated primary switch (Switch 1).<\/li>\n
- Set its priority to 15:
\n text
\n Switch(config)# switch 1 priority 15<\/code><\/li>\n- Power on the intended standby switch (Switch 2).<\/li>\n
- Set its priority to 14 so it will assume the standby role:
\n text
\n Switch(config)# switch 2 priority 14<\/code><\/li>\n- If physical member numbers do not match your rack layout, renumber members as required:
\n text
\n Switch# switch 1 renumber 2<\/code>
\n (Note: Renumbering requires a switch reload to take effect).<\/em><\/li>\n<\/ol>\n<\/span>Step 4: Sequenced Boot and Stack Convergence<\/span><\/h3>\n\n- Power on the remaining member switches.<\/li>\n
- Allow 3 to 5 minutes for the StackWise backplane arbitration and discovery process to complete.<\/li>\n<\/ol>\n
<\/span>Step 5: Validating Stack Health<\/span><\/h3>\nVerify stack status from the privileged EXEC prompt:<\/p>\n Switch# show switch\nSwitch\/Stack Mac Address : 00a3.d144.b200 - Local Mac Address\nMac persistency wait time: Indefinite\n H\/W Current\nSwitch# Role Mac Address Priority Ver State\n------------------------------------------------------------\n*1 Active 00a3.d144.b200 15 V02 Ready\n 2 Standby 00a3.d144.b280 14 V02 Ready\n 3 Member 00a3.d144.b300 1 V02 Ready\n<\/code><\/pre>\nVerify that the stack ring operates at full bandwidth:<\/p>\n Switch# show switch stack-ring detail\n\nSwitch Stack Ring Loopback Stack Ring Speed Frames Frames \nNumber Mode Type Status Rx Tx \n------------------------------------------------------------------\n1 Ring None Ok 480G 14209 14209 \n2 Ring None Ok 480G 15312 15312 \n3 Ring None Ok 480G 13980 13980 \n<\/code><\/pre>\nIf the Stack Ring Status<\/code> indicates Ok<\/code> and the topology displays Ring<\/code> (rather than Sub-Ring<\/code>), the stack is healthy and fully redundant.<\/p>\n
\n<\/span>Troubleshooting Stack Member Joining and IOS-XE Mismatches<\/span><\/h2>\nWhen a new or replacement switch is inserted into an existing Catalyst 9300 stack, it may fail to join the active topology. The two most common causes are software version discrepancies and license mismatches.<\/p>\n Switch# show switch\nSwitch# Role Mac Address Priority Ver State\n------------------------------------------------------------\n*1 Active 00a3.d144.b200 15 V02 Ready\n 2 Standby 00a3.d144.b280 14 V02 Ready\n 3 Member 00a3.d144.b400 1 0 V-Mismatch\n<\/code><\/pre>\n<\/span>Remediation Workflow for Version Mismatches (V-Mismatch)<\/span><\/h3>\nMethod A: Automated Remediation via Auto-Upgrade (Recommended)<\/h4>\nCisco IOS-XE features an auto-upgrade engine that leverages Install Mode to automatically push the target software version to the mismatched member.<\/p>\n \n- Ensure the active stack is running in Install Mode<\/strong> (indicated by the presence of
packages.conf<\/code> in flash):
\n text
\n Switch# show version | include Installation mode
\n Installation mode: INSTALL<\/code><\/li>\n- Enable automated software upgrades in global configuration mode:
\n text
\n Switch(config)# software auto-upgrade enable<\/code><\/li>\n- Alternatively, trigger the synchronization manually from privileged EXEC mode:
\n text
\n Switch# install autoupgrade<\/code><\/li>\n- The active switch detects the
V-Mismatch<\/code>, copies the matching binary packages to the new switch\u2019s flash partition, updates its boot variables, and triggers a localized reboot of that member slot.<\/li>\n<\/ol>\nMethod B: Manual Image Deployment via Install Mode<\/h4>\nIf automated upgrade is disabled or fails due to network module constraints, deploy the software package directly across all stack members:<\/p>\n \n- Copy the target
.bin<\/code> image to the active switch flash:
\n text
\n Switch# copy tftp:\/\/10.1.1.50\/cat9k_iosxe.17.12.04.SPA.bin flash:<\/code><\/li>\n- Run the
install add<\/code> command, committing the software to the stack:
\n text
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