Avatar of essexboy80
Flag for United Kingdom of Great Britain and Northern Ireland asked on

Cisco Switch - Redundancy

I wondered if somebody could offer some instance on moving to an HA configuration on my Cisco VLAN Switches (DMZ and Internet).

So we have a pair of Firewalls (Sonicwall NSA4600) that are running in active / passive HA mode, and then we have the Cisco 3750 Switches that have 5 VLANs on them.

On the Firewall my X2 Interface is divided into 4 VLANs (10, 20, 30, 50) and both of the Firewalls are connected downstream to Interfaces Gi1/0/23 and Gi1/0/24 (Primary Firewall -> Gi1/0/23, Secondary Firewall Gi1/0/24). These two interfaces are configured as Trunk Ports and then the interfaces are in VLANs as required.

We then have X3 on the Firewalls (Sonicwall Sonicpoints) connected to ports Gi1/0/8 and Gi1/0/9 on the Switch. We then have 6 access points in a VLAN 40 for this.

So I have got redundancy on my Firewalls, but what I don’t have is redundancy on the switches.

At present there is a switch configured below the live one, that is ready to go and if the primary switch fails we have to manually move all of the network leads across.

Can someone please assist with a better way for this to be done?

Thanks very much

Switches / Hubs

Avatar of undefined
Last Comment
Hamid Akbari

8/22/2022 - Mon

Stack up your switches and use NIC Teaming on your servers in conjuction with etherchannel on the switch (eg NIC A and NIC B on Server is teamed. Switch A and Switch B are stacked. Port 1 on SW A is bundled (etherchannell group) with Port 1 on SW B. NIC A connects to SW A-Port 1, NIC B connects to SW B-Port 1. If 1 switch fails, the server will not lose connection.

I hope this helps

Since your switches support stacking,  I agree that is the best method. My switches don't support stacking so I end HSRP to enable high availability at layer 2, and then failover NIC teaming for servers and I plus each firewall into a separate switches, so a switch failure would cause the connected firewall to become the passive one.


None of the connected devices are actually servers, they are access points or routers.

All of life is about relationships, and EE has made a viirtual community a real community. It lifts everyone's boat
William Peck

View this solution by signing up for a free trial.
Members can start a 7-Day free trial and enjoy unlimited access to the platform.
See Pricing Options
Start Free Trial
Ask your own question & get feedback from real experts
Find out why thousands trust the EE community with their toughest problems.

Hi Kevin,

I will post a diagram up hopefully this will then help

Hamid Akbari

We have tow aim of HA in switching

1-Port fail over : Aim-->increase availability and increase throughput
  you should use ether channel between servers and switches

2-Switch redundancy :Aim-->increase availability and provide fail over
You should use
Hardware solution:
*Stack-->in stack able switch is best solution (for Midsize network)
Software solution:
*VSS-->in High class switch (4500,6500) it is best solution(so better than Stack)
*GLBP-->if your switch support you can use weighted load balancing or round robin and host-dependent method.it is better than HSRP and VRRP.
*HSRP and VRRP-->HSRP:Cisco devices only and by default:premption:disable-->popular than VRRP
                                   VRRP:Standard and by default premption is enable

you can choose your scenario