HowToFixMe
IP / Network Issue

Extreme Networks switch: MAC table full

By Sai Kiran Pandrala · reviewed by Sai Kiran Pandrala, Editor Last verified: 2026-05-30

⚡ At a glance
VendorExtreme Networks
Operating systemEXOS / Switch Engine / VOSS
CategoryIP / Network Issue
Skill levelIntermediate to advanced
DIY-able?Yes with CLI access; some scenarios need Extreme GTAC + RMA.

What this guide covers

Real-world context. Budget honestly for ~Rs 0 INR under Extreme support, otherwise ~Rs 5,000 to Rs 80,000 INR for parts (around $60 to $960 USD), because the cheap path looks tempting until a part shows up wrong. You will burn ~20 to 60 minutes triage hands-on and roughly ~1 to 4 hours including failback once verification is done. Before you touch anything, line up the switch serial, an EXOS config backup, and console access, those three are what saves you when the first attempt does not stick.

Fix MAC table full on a Extreme Networks switch.

Step-by-step

  1. Check current MAC table utilisation.
  2. Identify the offending VLAN or port.
  3. Enable storm-control on access ports.
  4. Enable port-security with a hard MAC limit.
  5. Long-term, refresh to a switch with a larger MAC table.

CLI / commands

show ports info
show ports 1 description
show slot

When the issue persists

Frequently asked questions

Will this work on my specific EXOS / Switch Engine / VOSS version?

The procedure reflects current EXOS / Switch Engine / VOSS behaviour. Older releases may need minor syntax adjustments: use the CLI help (? or tab-completion) to verify.

Should I open a Extreme GTAC case immediately?

Open one if you suspect hardware failure or the symptom persists after a maintenance-window reload. Make sure your support entitlement is active first.

Where can I find the Extreme Networks official documentation?

https://extremeportal.force.com/ExtrArticleLanding, search the product family + feature name.

Is this procedure safe in production?

Test in a lab or maintenance window first. Capture pre-change state so you can roll back.

Related guides worth a look while you sort this one out:

References

Reference material, not professional advice. Validate against your specific EXOS / Switch Engine / VOSS version and test in a non-production environment before applying.

What changed recently?

Fault diagnosis on a Extreme device goes faster when you map the symptom to a recent change:

The answer narrows the root cause to a manageable subset.

Before you start

A few things to confirm so the Extreme device fix goes cleanly:

How to confirm it's actually fixed

On a Extreme device, the test is rarely "reboot and see". Use this list:

When to call Extreme support instead

Escalate if:

More frequently asked questions

Does this affect other devices on my network?

Generally no. The procedure is local to this device. Network-side changes (firmware updates that affect TLS, SMB, or routing) are flagged explicitly in the steps.

Will the procedure work on the international variant?

Some features and firmware paths are region-locked. Check the model spec sheet to confirm your variant supports the menu option referenced. If you're outside the US/EU, look for the regional support portal.

How often should I run preventive checks?

Quarterly for most consumer devices; monthly for production / commercial devices. Set a calendar reminder so the device stays healthy between issues.

Are there safer alternatives for non-technical users?

Yes: the manufacturer's self-service troubleshooter (HP Smart, LG ThinQ, Samsung Members, similar) usually walks through the same steps in a guided UI. Use that first if you're not comfortable with menu paths.

Is it safe to apply during business hours?

If the device is in production use, apply during a scheduled maintenance window. Most procedures need 2-15 minutes of downtime. Capture pre-change state so you can roll back if needed.