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Hi all,

I am planning to install this switch as a 24-port all SFP "core" switch in a relativly small office.

I am looking for the following information:

1) port-group mapping. When using all twingig convertor modules, which interfaces are connected to the same port-group asics ?

1-2 or 1-2-3-4, this for redundancy reasons

1b) If you plugin a Twingig in 10GE port 1, does the neighboring port also convert to 1G ? (some other cisco models have this "feature")

2) How many HSRP groups does the latest software support ?

3) MTBF as compared to C6504-E chassis and C3750G-12S switch.




Re: C3560E-12D-E

Hello Geert

2) How many HSRP groups does the latest software support ? - Its 32 for both 3650-E and 3750...

3) MTBF as compared to C6504-E chassis and C3750G-12S switch. - Information is given in the datasheet..

3560E-12D - 147,001 hours

3750G-12S - 215,000 hours

6504-E - 300,000 hours

I really didnt get your first question..

Hope this helps. Let us know



Re: C3560E-12D-E

MTBF is not so high and 32 HSRP groups is too limited for an 24p 1G SFP aggregation switch. You can't even connect 20 Access with Data and Voice VLAN (need 40 HSRP groups). Cisco..please fix :-)

If you are running 4 VLANs/access, you are stuck at 8 Access switches.

Re: C3560E-12D-E

Thats probably because 3750 and 3560s were more thought as edge switches where hsrp wouldnt be configured :) core switches such as 6500's can support upto 256 groups, which sounds a decent number.. not sure how much 4500 or 4900 supports, but they should hopefully be higher than 3750/3560 !!



Re: C3560E-12D-E

i have looked at the 4900M switch:

- Twingig convertors are not supported on the standard ports. You need to buy 2x 8-port halfblades. This gives 32 SFP 1G ports.

- And you need to buy the routing license.

- have not looked further in #HSRP groups

Price will be pretty close to a C6500 or C4500 chassis....

Re: C3560E-12D-E

Taking into consideration that this is a small office, my best bet would be to go with 3750-12 S, looking at both the cost, and features.. Stacking enhances the performance, within the cluster, unlike the 3560 and 4900 switches.. If you think that the office would grow, and need scalability, you can go in for a 6504E with SUP 32, which would cost a bit high, but has its own advantages.. that is a call which we have to make when designing networks :) and its upto you now :)


Super Bronze

Re: C3560E-12D-E

Like Raj, I too believe the 3750G-12S might be good choice.

Unlike the other 3750 series, the 3750G-12S supports additional SDM templates, with additional resources, to better serve as an aggregation device.

Compared to a small 6500, you get "sup" redundancy (each member switch can run the stack) and power redundancy (each member switch has its own power supply [2nd power feed an option with RPS]) without having to purchase chassis redundant components.

With the stack, you can multi-member etherchannel to other switches.

From a performance perspective, the 3750G-12S provides 17.8 Mpps (per stack member) and a 32 Gbps ring (dual 8 Gbps duplex). For 6500s, classic bus cards are provided 15 Mpps (per chassis) and 32 Gbps bus (16 Gbps duplex?).

Super Bronze

Re: C3560E-12D-E

". . . 32 HSRP groups is too limited . . ."

I've think so too, but since you can stack 3750s, and the VLAN IP will migrate to a new stack master, Cisco's thinking might be you don't really need them. Probably also why they don't support GLBP (I believe).

Of course, this doesn't help with the 3560 series, but if HSRP groups is an issue there's the 4900 series.

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