Application Delivery (ADX)

Reply
Contributor
Posts: 49
Registered: ‎04-24-2009

Is it possible to create an HA setup using different ADX models

Is it possible to create an HA setup using different ADX models

Super Contributor
Posts: 316
Registered: ‎05-01-2009

Re: Is it possible to create an HA setup using different ADX models

This is not possible. You are forced to use the same type of SI for both devices. Everything else is not supported and it is not going to work.

Contributor
Posts: 39
Registered: ‎05-04-2009

Re: Is it possible to create an HA setup using different ADX models

What do I configure in order to implement HA (High availability) with 2 ServerIron ADX's

Super Contributor
Posts: 316
Registered: ‎05-01-2009

Re: Is it possible to create an HA setup using different ADX models

This is not a simple question. There are multiple HA modes and it depends on your requirement and the software running at the ServerIron ADX. The different modes are:

Hot-standby:

This is only available using L2/Switch-Code. It is basically some kind of redundancy at the device level. One of the ServerIron's is going to be the master unit and this is the one processing ALL traffic. The other (backup) ServerIron is not forwarding any traffic. Both ServerIron's do use a dedicated (mandatory) heartbeat link to exchange session table details and to monitor the health status of the HA partner. The failover (master or backup status) of the HA pair is based on the amount of ports. The ADX with the higher amount of server + upstream facing ports is going to be the master and the other one is the backup device. A failover will occur in case a link goes down or in case a device goes down.

Hot-standby is pretty simple to configure - you are going to add a line like:

server backup ethe <port#> <MAC> vlan-id <VLAN>

to both ServerIrons - the <port#> is the port you would like to use as dedicated heartbeat port. <MAC> should be the MAC address of one of the ADX devices and <VLAN> is a heartbeat VLAN you have to create with the port <port#> in.

SSLB:

Symmetric-SLB - this is redundancy at a virtual server level. Each ADX might be responsible for some virtual servers backup up the virtual servers of the other ADX. Having 2 virtual servers you could put one of the at ADX #1 and one of them at ADX #2. Each one is backup up the others virtual server. This is getting done with so called "sym-priorities". Each virtual server does have its own sym-priority setting - the ADX with the higher sym-priority is going to be the master for the virtual server.

ADX #1:

server virtual myVirtA 192.168.100.101

  sym-priority 150

 

server virtual myVirtB 192.168.100.102.

sym-priority 100

 

ADX #2

server virtual myVirtA 192.168.100.101

  sym-priority 100

 

server virtual myVirtB 192.168.100.102.

sym-priority 150

 

This would result in ADX#1 being master for virtual server myVirtA and ADX#2 being backup for this virtual server. It is the other way around for myVirtB. Have a look at "dynamic sym priorities" in the documentation to learn how to change sym-priorities based on the health status of real servers/applications. The master for a virtual server is the one being able to process traffic for this virtual server.

Sym-Active SLB:

This is very similar to SSLB but BOTH ServerIrons are actually able to process traffic for ALL virtual servers. The sym-priority setting is still necessary and it is basically defining the ADX/ServerIron's responsible for the IP address (answering to ARP requests) but both ServerIron's are able to process traffic going to ALL of the virtual servers. Your upstream devices might use two routes to the virtual servers (one via ADX#1 and the other via ADX#2) and you could load balance in between both routes (think of ECMP) and the ADX which is getting the traffic is going to process it. Sym-active SLB is getting configured like SSLB but you have to add sym-active to the configuration:

ADX #1:

server virtual myVirtA 192.168.100.101

  sym-priority 150

  sym-active

 

server virtual myVirtB 192.168.100.102.

sym-priority 100

sym-active

 

ADX #2

server virtual myVirtA 192.168.100.101

  sym-priority 100

  sym-active

 

server virtual myVirtB 192.168.100.102.

sym-priority 150

sym-active

 

My personal recommendation would be to go for L3 code (PREM license) in case you would like to use SSLB or Sym-active as failover mechanism. L3 code is much more flexible in these areas and you can bind the virtual server failover to the VRRP(-E) failover and some other nice stuff.

I hope this helps.

Join the Community

Get quick and easy access to valuable resource designed to help you manage your Brocade Network.