We have 2 x cisco 6500 switches running as a core switches, recently one of the core failed and the other took over.. but this was not the issue.
The issue is we have a single DHCP server which was connected to the core which failed and hence there was an outage for all the end users, we don't have teaming configured on the DHCP server.
We are planning to add another DHCP server and connect it to the other core switch and add two IP helper-addresse under each SVI interfaces. This way we are not sure whether the client request would be sent to both the DHCP servers at the same? Ofcourse we don't want this...
If it works sequentially i.e, if the first DHCP is unavailable then it does go to the second.. this is fine but we are not sure whether it works in such a way.
Thanks for your mail, well.. dividing each subnet in two scopes is certainely a good idea and we may do that as well.
One other thing I wanted to know was.. if two ip helper-addresses are configured, in this case whether a client request would be sent to both the DHCP servers? or it would be sent to the first DHCP server as per the configuration sequence? an ex:
interface vlan 10
ip address 10.1.100.1 255.255.255.0
ip helper-address 10.1.101.10
ip helper-address 10.1.101.11
In this case when a client sends a request how the request would be forwarded? is it squentially, I mean first to 10.1.101.10 and if it is not available than to 10.1.101.11? OR to both at the same time?
In this case we will Install two DHCP servers with divided subnets.
So based on the understanding the DHCP server directly connected to the respective core may assign the ip address to the client and if one of the core fails the other assigns an ip address from a other part of the same scope or vice versa..
This is actually a pretty cool feature, i didn't even know it existed until I was looking for a solution to advertise a subnet (prefix in BGP talk), only if a certain condition existed. This is exactly what conditional advertisements does
j ai une question j ai achete un routeur cisco 887VA-k9 , je le configuré avec la configuration ci- dessous
si je le lier avec mon pc portable sur l un de ses ports directement ça marche toute est bien ( la connexion internet + m...
Attached policy provides CLI access to the Cisco 4G router over text messaging. Two files are in the attached .tar file:
2. PDF with instructions on how to load and use the .tcl file.