extending VLANs, non-trunking 1

[sonuteklists]

I recently acquired a rack mountable switch (non-Cisco, only for the price advantage). The main reason was to consolidate the wiring in a 42U rack full of servers. The
wires coming out of the rack was a real mess. Now our network architecture is segmented by a Cisco PIx 515E into 6 segments. These are connected to enterprise class Cisco
switch and ultimately to the jacks. As I said before the wiring to the rack was creating a mess and so we decided to house a rack mountable Gigabit switch. The swicth we
bought doesnt support VLAN trunking (again due to price), but it has 24 ports and supported all VLAN tags and other Cisco tags that was good enough for us.

The rack houses servers are connected to 3 segments/VLANS from the switch and since it doesnt support trunking I will have to have 3 connections from the Cisco switch into
this switch and create the similar VLANs on the new switch. I am pretty comfortable creating VLANs, assigning ports to VLANs, but what else should I do for the VLAN on this switch to properly connect to the VLANs of the Cisco switch. I understand the the VLAN on the Cisco swicth will be totally different from the VLANs I create on the new
siwtch, but what else .... I am a but consufed and am not sure if I have overlooked anything. How do I "match" a VLAN from the Cisco switch to the VLAN on the new switch.

Can anyone kinldy advice me of the proper procedure with some examples for all steps. Would greatly appreciate all advice.
Thanks a bunch.

 

[jneiberger]

If you're not doing trunking then you don't need to do anything else. Simply pretend that you have three small Cisco switches that you need to connect to three small non-Cisco switches. It's simple layer two connectivity. No need to confuse the issue.

By the way, was the savings worth the number of hassles you're running into? I'm having trouble believing you couldn't find a cheap switch that supported trunking. The market is loaded with 24-port switches that do trunking for cheap.

May I ask what brand of switch you bought?

 

[sonuteklists]

Its a Dell. This switch cost me around $500. Its a PowerConnect 3424. Also there were other features we desired like backing up configuraion which some other models I checked didnt support. Check the link for more features it supports,

http://www1.us.dell.com/content/products/productdetails.aspx/pwcnt_3424?c=us&cs=04&l=en&s=bsd

Its not too late yet if you can recommed some more enterprise class 24 port rack mountable switches comparable to the one I bought.
Thanks a bunch.

 

[hunterdw]

My $.02

For a few hundred more, a Dell 5224 / 5324 does gigabit (24 10/100/1000 4 SFP but you can only use 21-24 if you are not using the SFP - they are shared) and does support vlan trunking. Fully managed CLI although it's more clunky than IOS.

I think we paid $799 for our last one.

That said, I use my dell completely for a server farm. I don't use it for anythinig I need reliable QoS or anything on.

Dell 5224 / 5324 trunk port into a 3550 as I use it...

interface ethernet 1/22
switchport allowed vlan add 999 untagged
switchport native vlan 999
switchport allowed vlan remove 1
switchport mode trunk
switchport allowed vlan add 2-3,10,168,999 tagged

I don't use vlan 1, I use 999 for my "native"

2-3 are data, 10 voice, 168 public wifi

 

[sonuteklists]

Well, the quote they gave me for the 5324 was almost 1K, double the price of the 3424.
But could you kinldy check this link, it seemed a bit odd that it supported 802.1q but not trunking. From the following link for 3424, it seems like trunking might be possible with 3424.

http://support.dell.com/support/edocs/network/PC34xx/en...carriero.htm#1346043

Cross verify this with the following link for 5324,

http://docs.us.dell.com/support/edocs/network/pc5324/en/UG/switch.htm#1111518

Thanks.

 

[jneiberger]

What makes you think that the Dell switch can't do trunking? According to the documentation, it does support 802.1q trunking.

 

[sonuteklists]

I am sorry, I just went with what the Dell Tech (not the sales guy !!) said ... that the 3 series switches dont support trunking. I havent recieved the product yet and so couldnt check.

Now that we have verified that trunking is indeed supported, can you kindly tell me how do I "trunk" a connection to the Cisco switch from the Dell switch ?? I know the link does provide the command options, but could you kinldy provide the steps in brief with examples (general, CLI and not specific to Dell) ??

Thanks a bunch.

 

[jneiberger]

By whatever commands necessary (I'm not familiar with Dell switches), configure the switch so that the native VLAN is not tagged while other VLANs are tagged. Ensure that you're using the same native VLAN on both ends of the link.

 

[hunterdw]

The command I gave you above is your 802.1Q trunk command for the Dell.

It works. I use it now.

The command for the trunk on a Cisco switch is

interface GigabitEthernet0/1
switchport trunk encapsulation dot1q
switchport trunk native vlan 999
switchport mode trunk
end

So, my native vlan 999 is the same on both Cisco and Dell.

 

[sonuteklists]

hunterdw,
The trunk information has to "flow" from the Cisco switch to the Dell switch. Does that change anything in the commands you provided above ??

Why isnt a,
"switchport allowed vlan add 2-3,10,168,999 tagged"
command required on the Cisco switch ?? Different syntax ??
Shoudnt the allowed VLAN tag be set on the Cisco switch as that is where the VLANs are defined in the first place ??

One last stupid confirmation required. My native vlan is 1 on both the siwtches Cisco and Dell switch. I guess that should be ok, right ??
Thanks.

 

[sonuteklists]

I am sorry, one more,
Can I use the GigaBit Copper-connection on the Dell and any available connection (10/100 or Gigabit) connection on the Cisco switch for trunking.
Thanks a bunch.

 

[hunterdw]

No change.

the "switchport allowed vlan add 2-3,10,168,999 tagged" command is Dell CLI specific. Not IOS. Different syntax.

On the Cisco, the appropriate VLANs are tagged except the native vlan.

So, assuming you have your vlans configured correctly in vlan database (or other useful place), then all will be tagged on cisco correclty minus the native vlan.

The complicated part is the Dell which you have to specifically say whether it's tagged or not.

No worries about vlan1... that's fine.

Yes, also, you can use any connection two and from the Dell/Cisco.

I use the 1000SX GBIC on Cisco and SFP on Dell. But I've done it with RJ45 crossover too. They both work as long they are set as trunk ports.

You've got it.

 

[sonuteklists]

Just wanted post a few notes from the Dell configuration I did.
Firstly I added the required vlans to the database 10,11,12 (to match the VLANS from Cisco).
Then went into the g4 interface config and had to use the following commands,
# switchport mode trunk
# switchport trunk allowed vlan add 10,11,12
# switchport trunk native vlan 1

Kindly note the difference in syntax from the one you posted. Is this ok. It would not accept your format and also note that it would take the tagged after added vlan to trunk. Have I made any mistakes here ??

I havent yet done the config on the Cisco 5500 yet. I am pretty sure that would be ok.

I have one some more stupid questions,
- Is there any syncronization happening between the 2 dissimlar switches as regards VLAN traffic, like port 12 on Dell switch belongs to VLAN 10, port 12 Cisco switch belongs to VLAN 11.
- The Cisco switch has many more VLANs described, but after trunking a port on it, I will be allowing all VLANs "from it", but on the Dell switch I am only allowing VLANs 10,11,12 "into it". How will that matter or affect anything?
- What happens if I create new VLANs on the Dell switch and not create the same VLAN on the Cisco switch now ??

Kindly advice.
Thanks a bunch.

 

[sonuteklists]

I reason I asked about the sync is that I assumed there would be some syncing involved as I didnt exactly create IP subnets and such information for VLANs on the Dell switch. That information would come from the Cisco switch.
Can you kindly explain this process.
Thanks.

 

[hunterdw]

I'm not surprised it wouldn't accept my format. I'm on a 52xx series. You're on a 3424. I'm no Dell PowerConnect expert... I just have one in my Cisco AVVID network and needed to utilize it.

I can't speak to any VLAN synchronization as I don't know the network config you have.

I personally made my VTP database on the Dell separate.. on purpose. I didn't even try to "sync" VLANs using VTP between Cisco and Dell.

You need to make sure you have the same VTP database on the Dell and the Cisco. Whether you do that manually, or if you investigate whether you can "sync" them... that's up to you.

Sounds like you need to go offline this forum and go back to reading the Dell manual. They are useful. Dell also has great forums for their products... that, and you're on the Cisco Switch forum here...

Probably time to end this thread.

Good luck.

 

[sonuteklists]

Thanks a bunch for all the valuable info.

 

[sonuteklists]

Just wanted to end this thread with a useful link,

http://www.dell.com/downloads/global/products/pwcnt/en/app_note_4.pdf

Thanks.

 

[hunterdw]

Great info. Thanks for sharing.

--DW