Eliminate using STP?

kronicklez

Hi all expertise,


I need your advise regarding my new design. Currently I have EX4200 VC at each floor (Floor 1-34). At each VC have 4 VLAN. All of EX4200 will be connected to both Core Switch EX8208 (VC). For my new design i don't want to use STP. I want use OSPF. My Question now where i will configure default gateway for each VLAN? Is it at Core Switch or at Edge Switch itself. Currently if we using STP method default gateway will be configure at Core Switch right? How about if we use OSPF only? Can some explain with some example config. Thanks.....

mikej412

Sounds like you're doing a routed access solution. The Juniper solution doesn't look to different from the Cisco solution -- only the hardware and configs have changed (and no EIGRP routing option ).

You'll be routing down to the wiring closets. The VLANs (and subnets) should be contained in the individual wiring closets -- preferably to individual switches (or your virtual chassis).

You should be able to get some configuration ideas from this Juniper IMPLEMENTING L3 AT THE DATA CENTER ACCESS LAYER ON JUNIPER NETWORKS INFRASTRUCTURE PDF.

hoogen82

How about this... Easier Solution...

Juniper Networks :: Technical Documentation :: Example: Configuring Redundant Trunk Links for Faster Recovery

I think there some huge confusion on your or my part in understanding this...

You configure your vlans in the access... and then just add all the networks into the ospf protocol...

What do you mean my adding def gateway in core/access... I am assuming you are talking about management vlans??

I am not sure about why you want to run OSPF all the way till your access....That's probably not a good solution... Would love to hear your theory here though...

People use dynamic protocol... only if they have a three tier arch... core-distribution run the routing protocols... distribution-access still have all that good RSTP/MSTP stuff... More scalable and less burden in my opinion... And that's probably why Juniper came up with the RTG concept... very useful for setting up redundancy...

mikej412

hoogen82 wrote: »

I am not sure about why you want to run OSPF all the way till your access....That's probably not a good solution... Would love to hear your theory here though...

Routed Access designs are right up in popularity (and "hotness") with VSS Design Solutions in the Cisco World for Enterprise networks.

High Availability Campus Network Design--Routed Access Layer using EIGRP or OSPF [Design Zone for Campus] - Cisco Systems

The many potential advantages of using a Layer 3 access design include the following:
•Improved convergence
•Simplified multicast configuration
•Dynamic traffic load balancing
•Single control plane
•Single set of troubleshooting tools (for example, ping and traceroute)
Of these, perhaps the most significant is the improvement in network convergence times possible when using a routed access design configured with EIGRP or OSPF as the routing protocol. Comparing the convergence times for an optimal Layer 2 access design (either with a spanning tree loop or without a loop) against that of the Layer 3 access design, you can obtain a four-fold improvement in convergence times, from 800-900msec for the Layer 2 design to less than 200 msec for the Layer 3 access. (See Figure 4.)

<Figure 4>

Although the sub-second recovery times for the Layer 2 access designs are well within the bounds of tolerance for most enterprise networks, the ability to reduce convergence times to a sub-200 msec range is a significant advantage of the Layer 3 routed access design. To achieve the convergence times in the Layer 2 designs shown above, you must use the correct hierarchical design and tune HSRP/GLBP timers in combination with an optimal L2 spanning tree design. This differs from the Layer 3 campus, where it is necessary to use only the correct hierarchical routing design to achieve sub-200 msec convergence. The routed access design provides for a simplified high availability configuration.

kronicklez

Thanks for all person that reply n give feedback. At last has someone give some opinion. I read regarding that term "Routed Access" in Cisco so thats make me interested implementing to my new network using that kind of design because currently we use EX4200 as a Access Switch. Because of EX4200 have a capability to do a L3 so why not i using OSPF with VLAN. But in Juniper i don't find example of configuration such as Cisco documentation. I hope have some one have experienced that already implemented this type of design using Juniper can guide me. Thanks again.

kronicklez

mikej412 wrote: »

Sounds like you're doing a routed access solution. The Juniper solution doesn't look to different from the Cisco solution -- only the hardware and configs have changed (and no EIGRP routing option ).

You'll be routing down to the wiring closets. The VLANs (and subnets) should be contained in the individual wiring closets -- preferably to individual switches (or your virtual chassis).

You should be able to get some configuration ideas from this Juniper IMPLEMENTING L3 AT THE DATA CENTER ACCESS LAYER ON JUNIPER NETWORKS INFRASTRUCTURE PDF.

Hi Mike,


Thanks so much for this url. But in this URL it use MX. Is it same if i use EX8208 as a core Switch. Thanks.

mikej412

kronicklez wrote: »

But in this URL it use MX. Is it same if i use EX8208 as a core Switch.

When I checked the EX4200 and EX8208 data sheets to see what they could do, the 4200s looked like they'd act like a stack of Cisco 3750s and the 8208 looked like they'd take the Cisco 6500 role. You'd be using BFD to achieve the sub-second OSPF routing, so as long as we don't try a hybrid Cisco/Juniper solution, I don't see why the 8208s couldn't do it.

Since that PDF I did find on the Juniper site was for a data center solution, on the Cisco side we might use the Nexus Switches in the data center running NX-OS rather than the 6500s running IOS, so our configs would be different -- but the logic should stay the same. You might need to translate if there are differences between Juniper MX JUNOS and the EX's -- but you'd need someone more well versed in JUNOS (and Juniper hardware) than me to help you with that.

The most work would be if you're currently just running an L2 core with the EX8208s. If you're already running an L3 core with the EX8208s (OSPF area 0), then it should be easy bring L3 down to each individual wiring closet (each one is a separate OSPF area). Just make sure you've got a solution for any applications that are used across different floors that may require users being in the same VLAN or subnet. Same with security -- don't forget about any changes to any current security policies/configurations that could be needed as you isolate VLANs & subnets to individual wiring closets.

kronicklez

mikej412 wrote: »

When I checked the EX4200 and EX8208 data sheets to see what they could do, the 4200s looked like they'd act like a stack of Cisco 3750s and the 8208 looked like they'd take the Cisco 6500 role. You'd be using BFD to achieve the sub-second OSPF routing, so as long as we don't try a hybrid Cisco/Juniper solution, I don't see why the 8208s couldn't do it.

Since that PDF I did find on the Juniper site was for a data center solution, on the Cisco side we might use the Nexus Switches in the data center running NX-OS rather than the 6500s running IOS, so our configs would be different -- but the logic should stay the same. You might need to translate if there are differences between Juniper MX JUNOS and the EX's -- but you'd need someone more well versed in JUNOS (and Juniper hardware) than me to help you with that.

The most work would be if you're currently just running an L2 core with the EX8208s. If you're already running an L3 core with the EX8208s (OSPF area 0), then it should be easy bring L3 down to each individual wiring closet (each one is a separate OSPF area). Just make sure you've got a solution for any applications that are used across different floors that may require users being in the same VLAN or subnet. Same with security -- don't forget about any changes to any current security policies/configurations that could be needed as you isolate VLANs & subnets to individual wiring closets.

Hi Mike,


I'm very appreciate your advise. Thanks again. So now i have starting point how to use this kind of design.