Help setting up office for 100 percent uptime

[loveroots]

Dear expert I am task with setting up an office which should be up 100 percent. Office will have 80 users. I would like some help with this solution. I am thinking using the following

1) two 2851 routers
2) One MPLS link at 4.5 for primary and secondary link will be MPLS 1.5
3) Company routing protocol is OSPF ( Do i use HSRP and could you provide sample config and drawing to set this up)

 

[jeter]

Check out this Cisco web site....

http://www.cisco.com/en/US/tech/tk648/tk362/tk321/tsd_technology_support_sub-protocol_home.html

Go Army!
Tek-TIP Member 19,650

 

[whykap]

And don't forget your power requirements. I don't care how much redunduncy you have on the hardware if you do not have adequately designed power you will not achieve 100% up time.

 

[loveroots]

Hi Expert I was thinking on a design like below.I will have each router a a separte UPS.Do I need to have links with the same circuit size, and would I also be able to setup DMVPN from this site back to core network

======ISP======
I I *****link A 4.5M link B 1.5M
I**HSRP**I
rtrA rtrB *****Cisco 2851
I I
I I
=====LAN SWITCH==== **********Cisco 3560

 

[brianinms]

100 Uptime isn't possible .... but you can shoot for 5 9's.

 

[loveroots]

Hi Expert, Thanks for your explanation. My goal is to be able for office to still be up if a line cut happen or a fault with a cable pair. What I needed to know if when setting up a network as 5 9's could my secondary circuit be smaller, and would I be able to run OSPF with DMVPN and also HSRP for the 5 9's. would the cisco 2851 router support this ?

 

[brent87]

You can setup with your provider a fall over connection. The way it works to have two routers with the same speeds and they share the load. If one drops the traffic relays though the 2nd router. It can also work out cheaper this way because you are not paying for a fast line but to slower links that sharing the load.

 

[Belushi]

Don't forget about redundant entrances for the redundant circuits you will need in case of a cable cut. Also think about bringing the circuits in on some type of high availability type media like SONET. In either case, when your superiors see the cost of doing such a thing for 80 people, they may reconsider that 100% uptime mandate.

Also, I think it was mentioned before but you will need generator power, preferabbly by an external fuel burning generator. That won't be cheap. The cost of your redundant 2851 routers will seem like a drop inthe bucket.

Perceeption if never reality when it comes to uptime.

 

[burtsbees]

Total redundancy means no single point of failure---just go through all physical equipment and see. Everyone is right---what is the cost as compared to cost and probability of production loss through network downtime?

Burt