Network Switch Stacking Guide: Cisco StackWise vs HP Aruba VSF
When should you stack switches vs use traditional uplinks? Complete comparison of Cisco StackWise-480, StackWise-160, and Aruba VSF with cable requirements and
What Switch Stacking Actually Does
Switch stacking combines multiple physical switches into a single logical switch with one management IP address, one configuration file, and a unified control plane. Instead of managing eight individual switches in a wiring closet, you manage one stack. Port channels span across stack members, STP domains shrink, and failover between members happens in hardware rather than through reconvergence.
Stacking is not the same as uplink aggregation. When you connect switches via uplinks (even link aggregation / LACP), each switch remains an independent management entity with its own MAC table, STP instance, and configuration file. Stacking merges those entities into one.
Cisco StackWise Technologies
Cisco offers multiple stacking technologies depending on the platform. Getting the terminology straight prevents ordering the wrong cables.
| Technology | Platform | Bandwidth | Max Members | Cable Type |
|---|---|---|---|---|
| StackWise-480 | C9300 | 480 Gbps | 8 | STACK-T1 |
| StackWise-1T | C9300X | 1 Tbps | 8 | STACK-T4 |
| StackWise-160 | C3750-X, C3850 (legacy) | 160 Gbps | 8-9 | CAB-STACK |
| StackWise-320 | C9200 | 160 Gbps (half-ring) | 8 | STACK-T4-50CM (C9200-specific) |
| StackWise Virtual | C9500, C9400 | Uses uplink ports | 2 | Standard data cables |
Key Takeaway: StackWise-480 (STACK-T1 cables) is the standard for modern Catalyst 9300 deployments. If you are buying new, this is what you use. CAB-STACK cables are for legacy 3750-X and 3850 platforms only.
StackWise-480 Cable Options (C9300)
| Part Number | Length | Price Range |
|---|---|---|
| STACK-T1-50CM | 0.5 meter | $60 - $90 |
| STACK-T1-1M | 1 meter | $70 - $110 |
| STACK-T1-3M | 3 meters | $90 - $140 |
Each C9300 has two stacking ports. You connect them in a ring topology: Switch 1 Port A to Switch 2 Port B, Switch 2 Port A to Switch 3 Port B, and so on, with the last switch connecting back to Switch 1 to close the ring. A closed ring provides redundancy --- if one cable or member fails, the ring operates in half-ring mode without losing connectivity.
Search STACK-T1 for current pricing at Pro Disk Network.
Legacy StackWise-160 Cable Options (C3750-X, C3850)
| Part Number | Length | Price Range |
|---|---|---|
| CAB-STACK-50CM | 0.5 meter | $35 - $55 |
| CAB-STACK-1M | 1 meter | $40 - $65 |
| CAB-STACK-3M | 3 meters | $55 - $85 |
Search CAB-STACK for all legacy stacking cables.
StackWise Virtual (C9500)
StackWise Virtual is different from physical stacking. It uses standard data uplink ports (40G or 100G) to create a logical stack of exactly two C9500 chassis. There are no proprietary stacking cables --- you use QSFP+ or QSFP28 transceivers with standard fiber or DAC cables.
This approach is ideal for distribution and core layers where you want dual-chassis redundancy with single-management simplicity.
Aruba VSF (Virtual Switching Framework)
Aruba's stacking technology is called VSF (Virtual Switching Framework). It is available on the CX 6300 and CX 6200 series and uses standard SFP+ or QSFP+ uplink ports for the stacking interconnect --- no proprietary stacking cables required.
| Platform | VSF Interconnect | Max Members | Notes |
|---|---|---|---|
| CX 6300 | SFP+ (10G) or QSFP+ (40G) | 10 | Uses uplink ports, no dedicated stack ports |
| CX 6200 | SFP+ (10G) | 8 | Entry-level stacking |
How VSF Works:
- Designate specific uplink ports as VSF links
- Connect switches in a ring or chain topology using standard SFP+ DAC cables
- One switch becomes the conductor (primary), others become members
- The entire stack shares a single management IP and AOS-CX configuration
Pro Tip: Aruba VSF has a significant advantage: you do not need special cables. A $20 SFP-H10GB-CU3M DAC cable provides the same stacking interconnect that Cisco charges $90+ for with a proprietary STACK-T1 cable. For a 6-switch stack, that cable cost difference adds up.
Stacking vs Uplinks: When to Use Each
| Scenario | Recommendation | Why |
|---|---|---|
| Wiring closet with 2-8 access switches | Stack | Single management point, cross-member LAG, simpler STP |
| Distribution layer (2 switches) | StackWise Virtual or VSF | Dual-chassis redundancy, single config, no FHRP needed |
| Core layer (2 chassis) | StackWise Virtual | Simplified routing, single control plane |
| Switches in different buildings | Uplinks (LACP) | Stacking cables have length limits (typically 3m max) |
| Mixed vendors or mixed models | Uplinks | Stacking requires identical platforms |
| More than 8 switches in one closet | Uplinks for overflow | Stack member limits cap at 8-10 |
Key Takeaway: Stack when switches are physically close (same rack or adjacent racks in a wiring closet) and you want simplified management. Use uplinks when distance, vendor mixing, or scale exceeds stacking limits.
Cable Length Planning
Stacking cable length depends on physical switch placement:
- Same rack, adjacent switches: 0.5 meter cables
- Same rack, switches separated by 1-2U: 1 meter cables
- Adjacent racks (side by side): 3 meter cables
- Racks across a row: Not supported --- use uplinks instead
For Aruba VSF using DAC cables, the same distance rules apply. DAC cables max out at 5 meters for passive twinax. Beyond that, use active optical cables (AOC) or standard SFP+ transceivers with fiber.
Common Stacking Mistakes
- Open ring topology --- Not connecting the last switch back to the first. An open ring has no redundancy --- one cable failure splits the stack.
- Mixing stack cable generations --- Using CAB-STACK on one end and STACK-T1 on the other. These are incompatible.
- Exceeding member limits --- Adding a 9th switch to a C9300 stack (max 8) causes it to stay in standby.
- Not pre-provisioning --- Adding a new member to a running stack without pre-defining its role can cause temporary traffic disruption.
- Ignoring stack power --- In Cisco StackPower configurations, mismatched PSU wattages across members causes uneven PoE budgets.
Buy Stacking Cables at Pro Disk Network
We stock all Cisco stacking cables (STACK-T1, STACK-T4, CAB-STACK) and Aruba-compatible SFP+ DAC cables for VSF deployments. All cables ship same-day before 3 PM EST with free shipping on orders over $150.
Need help planning your stack? Email sales@prodisknetwork.com with your switch models and rack layout and we will recommend the right cables and lengths.