Recommended network setup?

Bookmage

Gawd
Joined
Sep 2, 2004
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673
Grab a drink cuz this is long

The Scenario:
So a while ago, we setup a new office and my inexperienced self had to setup the network. I understand the data side (mostly), but still don't have the practice I need for the VOIP/networking part.
We have 3 floors that we'll call floor 5,6,7. Our main server room w/racks is on floor 7 and our cables terminations end there. We'll have data and VOIP phones on all floors for 200-300 users, but most users on floor 6 and 7.
So we currently have Linksys SRW2048 Gig switches on the 5th floor connected to another SRW2048 on the 7th floor via a fiber connection. Internet comes in via a fiber cable to the SRW2048. The SRW2048 connects to a Cisco 24 port L3 Gig switch which handles all the vlans and routing. I'd like to move hte fiber drops to the Cisco switch, but the cisco SX SFPs didn't work... not sure if there's a setting on the cisco switch or what, but it wasn't plug and play like the linksys switch was...

The Issue:
I'm trying to optimize/prioritize VOIP calls and can't find much documentation on how to do this w/the Linksys switches. I have a separate VLAN for each floor and a VLAN for voice and wireless. I'd like to have all the phones on one subnet and all the wireless segmented off on another. One thing we'd like to do is use a wifi VOIP phone between floors, but that's yet to be implemented.

So what's the optimal way to setup the switches? all the cubicles/offices have at least 2 RJ45 ports, on/twoe for data and one for voice.

Option A: set all the ports to trunk and manually set the phones to a voice VLAN. This means I have to manually goto all the phones to set the VLANs, but would allow me to place phones in any jack.

Option B: Designate white ports to be voice and blue ports to be data and set all the linksys ports to the voice vlan. Leave one port on the linksys switch to trunk back to the Cisco switch. I don't have to manually set all the phones and the linksys switch is on a different vlan from the users. Downside is I have more to configure on the linksys switch, but at least I can use lcli for that. I set each port to General and designate the PVID to the voice VLAN. since I can't set a default trunk VLAN in the linksys switch.

Option C: Similar to Option B, but I set specific ports on the main Cisco switch to be voice and data and set the linksys ports to trunk. Less configuration on the linksys switches, but the switches are exposed on the user network.

I think I read the QOS on the cisco switch can only be set on the port and not on a vlan... not sure though...

What's the recommended best practices for implementing VOIP vlans in a network like this? We haven't purchased equipment for the middle floor, but the linksys switches are out of production. I'm lookin at the Dell 48port switches cuz the Cisco ones are too pricey...

Thanks,
 
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mattjw916

[H]ard|Gawd
Joined
Mar 10, 2005
Messages
1,289
I'd like to move hte fiber drops to the Cisco switch, but the cisco SX SFPs didn't work... not sure if there's a setting on the cisco switch or what, but it wasn't plug and play like the linksys switch was...
#media-type sfp (in interface config mode), it's probably set to rj45 if it wasn't working...

You don't set QoS on a VLAN because it's a per frame or per packet marking. Typically you're going to be marking voice as COS 5 at layer 2 (either the phone or the switch can be configured for this depending on what you have). I have no idea what the typical Linksys switch can do as far as prioritization goes since I really only work on high-end equipment.

With your limited experience I would say either a) hire an outside consultant to deploy your VoIP properly or b) stick all your phones in a dedicated VLAN on dedicated switches so you won't have to worry about complicated QoS settings.

Cisco switches are "pricey" because they can handle complicated QoS and about a thousand other things at the same time without breaking a sweat and you won't spend the rest of your life setting it up. Good luck with the Dell switches.
 

Bookmage

Gawd
Joined
Sep 2, 2004
Messages
673
cool thanks for the sfp command, I haven't had a chance to google that, but I figured it was something in the command line... does a cisco switch share the 4 fiber ports w/4 copper ports? or is it actually 4 extra ports? I remember seeing it go up to interface 28, but I wanted to make sure... (also havent had time to google that, and I just got an alert a drive in our file server is dying... :-/ )

There is QoS on the linksys switch, but I wasn't sure how that worked and the linksys documentation looks like it was written by congressman, lots of words, hard to decipher the practicalness...

Right now, I have all the phones in their vlan as an untagged port on the linksys switches. they're trunked back to the main cisco switch into a vlan...

and it seems overkill to pick up a cisco switch that can do a million things when we just need a switch to do less... but, that's not my call... all I can do is offer the best cheaper alternative I can find...

Thanks for the response... it's an ever learning process
 

mattjw916

[H]ard|Gawd
Joined
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Messages
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Some Cisco switches/modules have two different media-types available for the same physical interface. They are clearly labeled on the switch. For example gi0/8 on a 2960G has a big yellow box around an SFP port and an "RJ45" port. You can use one or the other but not both obviously and need to tell switch which transceiver to use using the media-type command.
 

Bookmage

Gawd
Joined
Sep 2, 2004
Messages
673
OK It goes up to port gi 0/28 and that is the fiber port.
There wasn't a media-type command which left me confused, so I checked the port status which showed err=disabled and checked the log and discoverred a crc error w/the transceiver. I googled around w/the error code and found the unsupported transceiver command. I enabled and after a short while, the lights came on and i could ping. So it looks like the brand cisco gbics aren't supported?
I wonder if they're the wrong type? or if the IOS needs to be updated...
 

mattjw916

[H]ard|Gawd
Joined
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1,289
To see which SFPs are supported for your model of switch go to the Cisco website and check the datasheet for it. There are numerous different types out there.
 
Joined
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Do you have closets on each floor or does all the cabling terminate on the main floor? How fast are the uplinks to the Cisco switch?
 

Bookmage

Gawd
Joined
Sep 2, 2004
Messages
673
The SFPs are on the Cisco approved list. That's why we got them. I heard somewhere that we probably need to update the IOS on it, so we're looking into that.

Each floor has a closet with switches there. Each floor is connected via a fiber uplink.
 

abyss1

Weaksauce
Joined
Apr 8, 2010
Messages
68
OK so most brands I work with can tag for both voice and data on the port. The linksys switches however I have no clue.

Doing some early googeling :
http://www.cisco.com/en/US/docs/swi.../administration/guide/SRW-US_v10_UG_A-Web.pdf

What I get from this is that these switches don't do dual vlan'ing on a port so you will have to set it on the phones. Most VOIP phones let you do that through their configuration.

Also the QoS settings seem rather static on the linksys switches , and might prove to be a challenge to get right. But I do assume you have a support contract on thoose things so you could always open a support case for implementation problems.

err disabled on CRC's can be a large lsit of issues from bad SFP to dirty fiber , can you test the connection any other way ?(I guess you dotn have a fiber cleaning kit ?)

And may I say that you seem I bit over tasked with the whole project. As someone suggested before this isnt to be taken lightly and I would suggest to ATLEAST get vendor support and probably a consultant over.
 
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