There's a couple of things that will help. First, VLANs will always contain broadcasts, that's why your PCs will only communicate when on the same VLAN. Second, in order for a host on one VLAN to communicate to a host on another VLAN, you must route between them.
The C3 has this ability to route, but you must set it up. The C3 also has the ability to be a DHCP server also. The manual (http://secure.enterasys.com/support/manuals/hardware/9034313-06_C3.pdf ) shows the router setup on section 18-1 (pg 515), and the DHCP setup in section 16-1 (pg 443). Here's the basic example steps to make this work... 1) create your vlans and assign them to ports set vlan create 2-3 set port vlan ge.1.1 2 set port vlan ge.1.2 3 set vlan egress 2-3 ge.1.24 tagged 2) create the router setup on one of the C3's router enable configure interface vlan 2 ip address 10.10.20.1 255.255.255.0 no shutdown interface vlan 3 ip address 10.10.30.1 255.255.255.0 no shutdown exit exit write file exit 3) create the DHCP scopes set dhcp enable set dhcp exclude 10.10.20.1 10.10.20.10 set dhcp exclude 10.10.30.1 10.10.30.10 set dhcp pool testvlan2 set dhcp pool testvlan2 dns-server 68.87.66.196 set dhcp pool testvlan2 default-router 10.10.20.1 set dhcp pool testvlan2 network 10.10.20.0 255.255.255.0 set dhcp pool testvlan3 set dhcp pool testvlan3 dns-server 68.87.66.196 set dhcp pool testvlan3 default-router 10.10.30.1 set dhcp pool testvlan3 network 10.10.30.0 255.255.255.0 Michael Votaw Phone: +1 405 216 8451 Mobile: +1 405 245 4617 e-mail: [email protected] "There is nothing more important than our customers." -----Original Message----- From: Victoir T Veibell [mailto:[email protected]] Sent: Thursday, June 11, 2009 12:45 PM To: Enterasys Customer Mailing List Subject: RE: [enterasys] Routing between VLANs Sorry, I forgot to state that when I put them in the same VLAN, I also changed their IPs to the same subnet. The problem has since been solved, however. We found that due to the lack of a DHCP server or any real DHCP services, my manual setting of the IP addresses and netmasks on the hosts was insufficient. I neglected to think about the fact that I needed to manually state the default gateway, and not just the default interface. So despite the fact that I could ping the gateway, and that the hosts would communicate whilst on the same subnet, they apparently did not automatically assume the default gateway based on the subnet mask. Once we corrected that everything began working as expected. It wasn't exactly an enterasys problem after all, just me assuming too much. Thank you all for your help, Victoir ---- Original message ---- >Date: Thu, 11 Jun 2009 15:29:22 +0100 >From: "Nick Allen" <[email protected]> >Subject: RE: [enterasys] Routing between VLANs >To: "Enterasys Customer Mailing List" <[email protected]> > >Why not post your configs and maybe a screenshot of your IP settings on >your computers (ipconfig / ifconfig). > >One thing that perplexed me with your initial email was this: > >--- snip --- >Computer --> Switch -- > Switch --> Computer. >VLAN2 --> --> --> VLAN3 >VLAN2: 10.10.20.1/24 >VLAN3: 10.10.30.1/24 >Computer 1: 10.10.20.100 >Computer 2: 10.10.30.100 >When both computers are on VLAN2 together, they can communicate just >fine >--- snip --- > >Surely if your computers were configured as you detailed above, and both >in the same VLAN, then they shouldn't have been able to communicate over >IP since there was no routing set up, yet you stated "they can >communicate just fine", which makes me wonder if your computers subnet >masks were incorrect for example. > >Just a thought. > >Nick. > > > >Nick Allen >IT Director > >TBWA\GROUP >76-80 Whitfield Street >London, W1T 4EZ >Direct: +44 20 7573 6792 >Mobile: +44 7970 121 609 > >www.tbwa-london.com > >This e-mail is intended only for the named person or entity to which it is >addressed and >contains valuable business information that is proprietary, privileged, >confidential and/or >otherwise protected from disclosure. If you received this e-mail in error, any >review, use, >dissemination, distribution or copying of this e-mail is strictly prohibited. >Please notify >us immediately of the error via e-mail to [email protected] and >please delete >the e-mail from your system, retaining no copies in any media. We appreciate >your cooperation. > > >Reg. Office: TBWA UK GROUP Ltd, 76-80 Whitfield Street, London, W1T 4EZ > >Company Reg. #: 4332188 (UK) >Company VAT #: GB 656 8994 61 > >-----Original Message----- >From: Victoir T Veibell [mailto:[email protected]] >Sent: 11 June 2009 15:14 >To: Enterasys Customer Mailing List >Subject: Re: [enterasys] Routing between VLANs > >Thank you all for your responses so far. I've spent a few days digging >through the manual looking at commands and when that failed, turned >here. So far everything that has been suggested is either (I think) more >than what I'm looking for at the moment (gateway of last resort, DHCP >servers, etc) or something I've already done/tried. The trunking is all >set up just like you all have specified, as has the port setup and >routing setup (minus, in one case, the ip helper address for a DHCP >server). To simplify the problem, I dropped it down to one switch so >now one host comes in on ge.1.1 on VLAN2, and the other host comes in on >ge.1.2 on VLAN3 on the same C3 switch. Nothing else is connected. The >subnets are still the same: >VLAN2: 10.10.20.1/24 >VLAN3: 10.10.30.1/24 >Host 1: 10.10.20.100 >Host 2: 10.10.30.100 > >All interfaces are administratively up, and VLANs 2 and 3 are >operationally up. Both ge.1.1 and ge.1.2 have VLANs 1 and 2 untagged in >the egress list (and I've tried it with only that ports VLAN in the >list). The MAC and ARP tables still see both hosts, and it still refuses >to route traffic between subnets. Both computers can ping their >respective gateways, but not the gateway of the other subnet. I really >feel like I'm missing some small part that makes this all work. > >Thanks again for your help, >Victoir > >---- Original message ---- >>Date: Wed, 10 Jun 2009 23:15:07 -0400 >>From: "Francisco Garcia Alvarez" <[email protected]> >>Subject: Re: [enterasys] Routing between VLANs >>To: "Enterasys Customer Mailing List" <[email protected]> >> >> Angela is right; in order to communicate VLANS you >> need routing interfaces that forward data from one >> network to another. For the exact commands, please >> go to the C3 admin guide; is pretty easy going. >> Francisco J Glvarez >> Administrador Redes >> Directa Inftica >> Rama Judicial Puerto Rico >> (939)389-3059 >> [email protected] >> >> ----- Original Message ----- >> From: Victoir T Veibell <[email protected]> >> To: Enterasys Customer Mailing List >> <[email protected]> >> Sent: Wed Jun 10 17:01:35 2009 >> Subject: Re: [enterasys] Routing between VLANs >> >> I'm using two C3 series switches. I was hoping the >> switches would limit broadcast traffic but still >> allow communication over seperate VLANs by >> transferring packets over egress ports until >> reaching the switch that was directly connected to >> the destination, and then automatically route it to >> the new subnet/VLAN based on ARP tables. Admittedly >> I've not been entirely sure how that part works and >> was hoping it was similar to communication between >> subnets over separate router interfaces. In this >> case I want to separate offices and organizational >> groups by VLAN, but still allow everyone access to a >> few central data servers on a seperate VLAN. What is >> the best way to go about this? >> >> ---- Original message ---- >> >Date: Wed, 10 Jun 2009 15:39:48 -0500 >> >From: Angela K Hollman <[email protected]> >> >Subject: Re: [enterasys] Routing between VLANs >> >To: "Enterasys Customer Mailing List" >> <[email protected]> >> > >> > How are you routing between the vlans? You will >> need >> > some sort of routing device for communication >> > between vlans. You will be able to accomplish >> the >> > routing on the switch if it is a C3 or N-series. >> > >> > The purpose of vlans on switches is traffic >> > separation so the vlans are operating as >> designed. >> > >> > _________________ >> > Angela K. Hollman >> > Information Technology Services >> > Network Manager >> > (308)865-8176 >> > >> > From: "Victoir T Veibell" >> <[email protected]> >> > To: "Enterasys Customer Mailing >> List" >> > >> <[email protected]> >> > Date: 06/10/2009 03:29 >> PM >> > Subject: [enterasys] Routing between >> VLANs >> > >> > >> ------------------------------------------------ >> > >> > Hello all. >> > I'm using two L3 switches in (what I had hoped >> would >> > be) a basic test. The setup is something like >> this: >> > Computer --> Switch -- > Switch --> Computer. >> > VLAN2 --> --> --> VLAN3 >> > VLAN2: 10.10.20.1/24 >> > VLAN3: 10.10.30.1/24 >> > Computer 1: 10.10.20.100 >> > Computer 2: 10.10.30.100 >> > >> > When both computers are on VLAN2 together, they >> can >> > communicate just fine. When I change one over >> into >> > VLAN3, however, they stop. Both switches still >> see >> > both computers with the "show ip arp" and "show >> mac" >> > commands, they just refuse to transmit packets >> > through. >> > Each computer is on ge.1.1, and both switches >> have >> > ge.1.1 set to the computers respective VLAN with >> the >> > opposite VLAN as a tagged egress VLAN. The trunk >> > between switches has both VLAN2 and 3 as egress >> > VLANs. I should also note that this behavior >> > continues when I use only one switch, and leave >> out >> > the trunk altogether. >> > Since the problem only starts when I change one >> into >> > a seperate VLAN, I assume the problem is either >> with >> > my egress settings or the switches are somehow >> not >> > transferring the packets between subnets/VLANs. >> Is >> > there a non-default protocol I'm missing or >> > something that would create this issue? >> > >> > Thanks, >> > Victoir >> > --- >> > To unsubscribe from enterasys, send email to >> > [email protected] with the body: unsubscribe >> > enterasys [email protected] >> > >> > * --To unsubscribe from enterasys, send email >> to >> > [email protected] with the body: unsubscribe >> > enterasys [email protected] >> >> --- >> To unsubscribe from enterasys, send email to >> [email protected] with the body: unsubscribe >> enterasys [email protected] >> >> * --To unsubscribe from enterasys, send email to >> [email protected] with the body: unsubscribe >> enterasys [email protected] > > >--- >To unsubscribe from enterasys, send email to [email protected] with the >body: unsubscribe enterasys [email protected] > > > > >--- >To unsubscribe from enterasys, send email to [email protected] with the body: >unsubscribe enterasys [email protected] --- To unsubscribe from enterasys, send email to [email protected] with the body: unsubscribe enterasys [email protected] --- To unsubscribe from enterasys, send email to [email protected] with the body: unsubscribe enterasys [email protected]
