Topic 'Replaceing three switchs with one' in forum 'Wireless Service Providers' - dslreports.com

Re: Replaceing three switchs with one

Thu, 02 Jul 2009 06:18:41 EDT

Equis posted : Hello Rhaas

Thank you for that.

Re: Replaceing three switchs with one

Thu, 02 Jul 2009 02:50:25 EDT

Rhaas posted : Vlan 1 is generally the default untagged vlan on most managed switches. You don't necessarily need to tag traffic as Vlan 1 coming from the router as untagged traffic on that port will default to vlan 1 on the switch (usually).

What you are looking at doing is exactly what I've done here: »This morning's fun You wont have any issue with MTU or OSPF in this setup.

Here is the relevant config from the above setup:
MT:

/interface vlanadd arp=enabled comment="" disabled=no interface=Core_Switch mtu=1500 name=Bernie_Canopy use-service-tag=no vlan-id=20add arp=enabled comment="" disabled=no interface=Core_Switch mtu=1500 name=Campbell_Canopy use-service-tag=no vlan-id=21add arp=enabled comment="" disabled=no interface=Core_Switch mtu=1500 name=MHS_Redline use-service-tag=no vlan-id=22add arp=enabled comment="" disabled=no interface=Core_Switch mtu=1500 name=Risco_Redline use-service-tag=no vlan-id=23add arp=enabled comment="" disabled=no interface=Core_Switch mtu=1500 name=Canopy_900 use-service-tag=no vlan-id=24add arp=enabled comment="" disabled=no interface=Core_Switch mtu=1500 name=Waveip_700 use-service-tag=no vlan-id=25add arp=enabled comment="" disabled=no interface=Core_Switch mtu=1500 name=VSW use-service-tag=no vlan-id=26add arp=enabled comment="" disabled=no interface=Core_Switch mtu=1500 name=Vertical use-service-tag=no vlan-id=27add arp=enabled comment="" disabled=no interface=Core_Switch mtu=1500 name=Horizontal use-service-tag=no vlan-id=28add arp=enabled comment="" disabled=no interface=Core_Switch mtu=1500 name=Servers use-service-tag=no vlan-id=40add arp=enabled comment="" disabled=no interface=Core_Switch mtu=1500 name=HSW use-service-tag=no vlan-id=29

And from the Cisco Switch:

!interface FastEthernet0/1 description To_Router switchport trunk encapsulation dot1q switchport trunk allowed vlan 1,20-29,40,1002-1005 switchport mode trunk no cdp enable!interface FastEthernet0/2 description To_Servers_Switch switchport access vlan 40!interface FastEthernet0/3!interface FastEthernet0/4!interface FastEthernet0/5!interface FastEthernet0/6!interface FastEthernet0/7!interface FastEthernet0/8!interface FastEthernet0/9!interface FastEthernet0/10!interface FastEthernet0/11!interface FastEthernet0/12!interface FastEthernet0/13!interface FastEthernet0/14!interface FastEthernet0/15 description HSW switchport access vlan 29!interface FastEthernet0/16 description Horizontal switchport access vlan 28!interface FastEthernet0/17 description Vertical switchport access vlan 27!interface FastEthernet0/18 description VSW switchport access vlan 26!interface FastEthernet0/19 description Waveip_700 switchport access vlan 25!interface FastEthernet0/20 description Canopy_900 switchport access vlan 24!interface FastEthernet0/21 description Risco_Redline switchport access vlan 23!interface FastEthernet0/22 description MHS_Redline switchport access vlan 22!interface FastEthernet0/23 description Campbell_Canopy switchport access vlan 21!interface FastEthernet0/24 description Bernie_Canopy switchport access vlan 20!

On the MT the interface named 'Core_Switch' is the physical interface that is connected to port #1 on the switch. Personally I don't assign any ip address to that port as I use tagged traffic for management. Anything you assign to the physical interface as far as ip addresses etc. will equate to untagged traffic and will use the native/default vlan on the switch (usually vlan 1). Each Vlan interface can be manipulated just like it was a physical interface on the router.

On the switch port #1 is setup as a trunk port so that multiple tagged vlan traffic can pass and exiting traffic is tagged with the appropriate vlan. Subsequent ports are set as access ports (un-tagged).

So Using HSW (Horizontal South West access point) as an example from my configs. If you look at the MT config you'll see I have HSW assigned to vlan 29. Then looking at the cisco config you'll see that port 15 is set to access vlan #29 and my HSW access point is plugged into that port. My HSW access point does not tag it's traffic.

Re: Replaceing three switchs with one

Thu, 02 Jul 2009 00:07:03 EDT

davebc posted :

said by Equis:

So if I have Vlan1 on teh switch I don't need to create Vlan1 on my mikrotik router for example?

You don't have to if you don't mind taking up extra switch ports.

Re: Replaceing three switchs with one

Wed, 01 Jul 2009 22:12:23 EDT

Equis posted : So if I have Vlan1 on teh switch I don't need to create Vlan1 on my mikrotik router for example?

Thanks

Re: Replaceing three switchs with one

Wed, 01 Jul 2009 21:17:57 EDT

battleop posted : The devices do not care about Vlans. If you create a Vlan in a switch and put ports in that vlan it's like having multiple switches in one box.

Re: Replaceing three switchs with one

Wed, 01 Jul 2009 19:01:57 EDT

Equis posted : OK, Thanks

Will OSPF still work fine?
Any other gotcha's I need to worry about? (MTU etc?)

I have never really done Vlans much before.

Thanks again

Re: Replaceing three switchs with one

Wed, 01 Jul 2009 17:49:17 EDT

scobywhru posted : The default VLAN or untagged VLAN for an interface is the LAN the devices will see devices that support VLAN tags will only see which ones you pass to that interface from the switch.

Re: Replaceing three switchs with one

Wed, 01 Jul 2009 17:31:05 EDT

Rhaas posted : The servers don't have to support Vlan tags, only the switch & router. Think of it as creating virtual interfaces on your router.

Re: Replaceing three switchs with one

Wed, 01 Jul 2009 17:02:52 EDT

Equis posted : Thanks

Some of the servers/devices don't support Vlans.

I could do some tho

Thanks

:-)

Re: Replaceing three switchs with one

Wed, 01 Jul 2009 10:36:45 EDT

Rhaas posted : You can can do that, there are some caveats obviously to doing this, you may end up with a route cache issue and depending on what you are doing on the individual interfaces (ie dhcp server, ospf) you may have some service conflicts.

I would do it with Vlan's.

Re: Replaceing three switchs with one

Wed, 01 Jul 2009 08:59:36 EDT

battleop posted : Why wouldn't you want to use vlans for this?

Replaceing three switchs with one

Wed, 01 Jul 2009 03:05:48 EDT

Equis posted : Hello

I have a a router with 3 interfaces going to three switch.

one transit, one customer and one servers.

I was thinking of just having all interfaces going into one big switch.
I don't want to use Vlans or anything, I can't see a need.

Is there any issues with doing this?

Thanks

:-)