upgrading from cat 3550 to 3750

[prakavi]

we have   two core swiches 6506 and  around 55 cat 3550 switches. currently we are on the process of replacing   the cat 3550 switches to 3750 switches.We need 10/1000/1000  speed, ip base image with upgrade options. Our up links from cat 3550s(sfps) are  single mode and  dual mode fiber  mode with 1 gbps  ports on core switch.

At present we are not upgrading to 10 gb modules  on core. Spread over 15 floors  each floor needs  2 up links(single mode , and dual mode). since cat 3750  sfps are smaller in size existing  gibics cannot be used. Looking for the best option of cat 3750 switches with 1 gb up links which can be  upgraded to 10 gb later  when we replace the  modle on core.Can any one guide me?

Requirements:

1- Cat 3750 switches 55 in no with sfps for 1 gb up link (dual mode fiber and  single mode fiber)

2- stacking option

3- 10/100/1000  speed

4- ip base image upgradable  to ip service image

5- ipv6  compatibaility. Network is spread over 15 floors so from each floor  we need two sfp  up links 1 gbps  using dual mode and single mode

-6-Should be upgradable to 10 gb  in future when we upgrade  the core modules

Or is it better to go for 10 gb module in core as well as  edge switches ? if so what should be the modules?

Regards

prakavi

[Reza Sharifi · Accepted solution]

Hi,

You can use the 3750X series switches.  The uplinks are modular, so for now you can get a 1Gig SFP based module and later when you want to upgrade to 10Gig, you can simply replace the 1Gig module with 10Gig. Since your fiber is single mode, make sure to order single mode SFPs.

Here is the data sheet:

http://www.cisco.com/en/US/prod/collateral/switches/ps5718/ps6406/data_sheet_c78-584733.html

HTH

[prakavi]

Thanks for the reply. Can I use the existing  connectors (sfp)  single mode /dual mode   in the new switch es? Or Shall I have to buy new sfp gibics for the 3750s?  is it mandatory to have  ip service iamge  for inter vlan routing ?Please calrify

Regards

[Leo Laohoo]

Thanks for the reply. Can I use the existing  connectors (sfp)  single mode /dual mode   in the new switch es?

You want to use the same fibre optic patch cable?  Sure, if one end is LC (SFP side).

is it mandatory to have  ip service iamge  for inter vlan routing ?

Depends on what routing protocols you are planning to use.

RIPv1, RIPv2, IS-IS, OSPFv1 is supported in IP Base.

[Joseph W. Doherty]

Disclaimer

The   Author of this posting offers the information contained within this   posting without consideration and with the reader's understanding that   there's no implied or expressed suitability or fitness for any purpose.   Information provided is for informational purposes only and should not   be construed as rendering professional advice of any kind. Usage of  this  posting's information is solely at reader's own risk.

Liability Disclaimer

In   no event shall Author be liable for any damages whatsoever (including,   without limitation, damages for loss of use, data or profit) arising  out  of the use or inability to use the posting's information even if  Author  has been advised of the possibility of such damage.

Posting

prakavi wrote:
 Thanks for the reply. Can I use the existing  connectors (sfp)  single mode /dual mode   in the new switch es? Or Shall I have to buy new sfp gibics for the 3750s?  is it mandatory to have  ip service iamge  for inter vlan routing ?Please calrify
Regards

You'll need new optics modules, i.e. the SFPs.

As to requiring more than IP Base for routing, base image supports statics and RIP (including v2), OSPF or EIGRP would need service image.

In the original series, it was possible to run a whole stack on just one stack member with upgraded license, don't believe this is true with -X series.

PS:

BTW, since you mention IPv6, do know that 3750s (including the latest -X?) have limited TCAM resources.  This often isn't too much of a problem if you use the most appropriate SDM template, but using IPv6, I understand, increases the TCAM pressure.

[Reza Sharifi · Accepted solution]

Hi,

3550 take GBIC with SC type connector.  3750x take SFP with LC type connector.

So, if you upgrade to 3750 (1Gig), you need to purchase the SFPs and also the fiber patch cords with LC type connectors.

don't forget if your fiber is single mode you need single mode SFPs if your fiber is multimode you need multimode SFPs.

The part numbers are

"GLC-SX-MM" for multimode

and

"GLC-LH-SM" for single mode

for more info see table-8 in this link:

http://www.cisco.com/en/US/prod/collateral/switches/ps5718/ps6406/qa_c67-578933_ps10744_Products_Q_and_A_Item.html

HTH

[prakavi]

if 10 gb sfps are used can I use  LR  and LRM modules? What should be the corresponding ones in the core switch? Assuming  each floor requires  two up links (15 floors)  .  Core is 6506  .

Regards

[Leo Laohoo]

if 10 gb sfps are used can I use  LR  and LRM modules? What should be the corresponding ones in the core switch?

The question is not whether you can use LR or LRM modules.  The question is the distance.  If it's too short and you are using LR/LRM modules, then there's a chance that you could "burn" the optics of the very-expensive SFP/SFP+.

I mean, you "can" generally use it but if the optics get burned because you are shooting laser at a powerful level then you'll need to pay for replacement because I'm sure no manufacturer will guarantee that.

[Reza Sharifi · Accepted solution]

If your fiber is single mode, use LR on both sides of the connection

Part number for the 3750 side

SFP-10G-LR

part number for the 6500 side:

X2-10GB-LR

Remember, if you are connecting these devices together back-to-back, you need LC to SC patch cord

HTH

[Leo Laohoo]

2- stacking option

In addition to Reza's post, please DO NOT be tempted to stack 7 or more 3750X into a single stack.  I personally recommend up to 6 switches in a stack.

[prakavi]

Hi,

Can a 10 gb sfp and 1 gb sfp can co- exist ? So the the primary  up-link can be 10 gb and and secondary can be  1 gb dual mode. Is it possible ? lr module and  glc-sx-mm module ?

Regards

pradeep

[Reza Sharifi]

Hi,

Although, not very common in a good design, but yes, it is possible to have a 10Gig uplink and a 1Gig uplink.

If you do it this way you can't create an Etherchannel, because of duplex and speed mismatch.  You have to run spanning tree.

lr module and  glc-sx-mm module

Yes

Reza

[prakavi]

Hi Reza,

How many uplinks (1 gb and 10gb) are avilable for catalyst 3750-x-24ps? I mean built in ? We are planning to add C3KX-NM-10G  module  so that we  can later switch over to 10 gb  sfps. Is it mandatory to buy this modules or does it come by default in the switch? We require 15 uplinks single mode fiber and 15 up links dual mode fiber.

In this case we have to buy 15 c3kx-nm-10 gb modules which supports 2 sfp plus and 2 sfps. we require around 55 switches  spread over 15 floors. So from every floor two uplinks are required. if  this module comes by default we dont have to purchase it . on the other hand 15 network moules to be added.Kindly clarify

Regards

[Joseph W. Doherty]

Disclaimer

The    Author of this posting offers the information contained within this    posting without consideration and with the reader's understanding that    there's no implied or expressed suitability or fitness for any  purpose.   Information provided is for informational purposes only and  should not   be construed as rendering professional advice of any kind.  Usage of  this  posting's information is solely at reader's own risk.

Liability Disclaimer

In    no event shall Author be liable for any damages whatsoever  (including,   without limitation, damages for loss of use, data or  profit) arising  out  of the use or inability to use the posting's  information even if  Author  has been advised of the possibility of such  damage.

Posting

prakavi wrote:
How many uplinks (1 gb and 10gb) are avilable for catalyst 3750-x-24ps? I mean built in ? We are planning to add C3KX-NM-10G  module  so that we  can later switch over to 10 gb  sfps. Is it mandatory to buy this modules or does it come by default in the switch? We require 15 uplinks single mode fiber and 15 up links dual mode fiber.
In this case we have to buy 15 c3kx-nm-10 gb modules which supports 2 sfp plus and 2 sfps. we require around 55 switches  spread over 15 floors. So from every floor two uplinks are required. if  this module comes by default we dont have to purchase it . on the other hand 15 network moules to be added.Kindly clarify

Network/Service Modules are optional - i.e. an extra cost option.

The nm-10g, as you note, supports 2 SFP (gig) and 2 SFP+ (10g).  (You can also use the SFP+, I recall, for gig, but with some conditions.)