Standby Question

[encarter]

We had a Consultant come into to implement VoIP at our office and on the side he configured Vlans for our wireless network as I have no Cisco experience as i am currently learning.

Anyway i wondered if someone could explain this piece of code. I created a new VLAN on my Layer 3 switch. First i just assigned the IP address and the DHCP server, but i couldnt ping anything *until* i added the standby lines that the consultant did for the other VLAN's. As soon as i did add the standby lines it worked?

Why would i need to add a standby IP for the routing to work, i thought standby was a rundant setting, not essistenial.

??

----------

interface Vlan60
ip address 192.90.12.196 255.255.255.192
ip helper-address 192.90.10.32
standby 50 ip 192.90.12.193
standby 50 priority 110
standby 50 preempt

-----------

 

[NettableWalker]

The standby lines tell you that he has configured HSRP.

The IP address 192.90.12.193 is the IP address of the "virtual router" group that behaves like a router. If one of the group fails another one will take up the role. The rest of the lines just tune HSRP.


I would take off the preempt line if it is already con figured on another router/switch as they both might try to preempt in the event of a recovery from a failure.

MCP,CCA,CCNA, Net+, Half CCNP...

 

[UnaBomber]

The preempt is fine, as it will make the router with the highest priority take precedence, if they are the same then the router with the highest ip address takes priority:

http://www.cisco.com/warp/public/619/6.html

Why would i need to add a standby IP for the routing to work, i thought standby was a rundant setting, not essistenial.

Standby is a setting for redundancy. I'm just wondering what the priority and IP address of the other layer 3 int is on your switch? Do you have any arp entries for the real ip address on int vlan60?

 

[encarter]

Thanks for the response guys.

UnaBomber hit my main question at the bottom of his post.
I understand the main objective of HSRP however i dont see why i could'nt route data over that VLAN until i specifically set standby IP.

On my other L3 switch i just have:

interface Vlan60
ip address 192.90.12.196 255.255.255.192
ip helper-address 192.90.10.32

How do i find the priority and IP addy of the other L3 int on the other switch?

Isnt the real addy 192.90.12.196, unaBomber

 

[UnaBomber]

You have both your vlan interfaces with the same physical ip address, and within the same vlan?

Yes 192.90.12.196 is the physical ip address.

I thought you said you had hsrp config'ed on all your VLAN ints?

 

[encarter]

To your first question Yes. Both VLAN60's on both of the L3 Switches are configured with the same Physical IP. I take it that isnt good practise??

And to your second question I have no idea if HSRP is config'd on all my VLAN ints? How would i tell?