VLANs: To be or not to be [7:58350]
Hello group, I was wondering about the following question: Is worth to implement VLANs and L3-switching instead a flat L2-network? I know that this question has been discussed here several times, but the answer is always the same: depends. What I would like to know is if sombody has implemented a L3-switched network following the "Cisco style" (Core-distribution-access or collapsed core-access) and now the performance is better than with a L2 network. I had an experience with a network (about 1000 users) with VLANs and Alcatel L3-switches that was terribly slow when you tried to transfer files between VLANs so the staff decided migrate to a flat network, that increased the network performance noticeably. Do you have real experiences or links talking about real experiences that I can check? Thanks and advance. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=58350&t=58350 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: VLANs: To be or not to be [7:58350]
I have first hand knowledge, we have implemented a core/dist/access network at cisco with L3 at the core and L2 at the acess end. I have also implemented a L3 data center using L3 dist routers and L2 access to the servers. This design, from switch to switch across the L3 dist area, is 1ms or less in the data center and only a couple of ms from most points in the core to most points in the dist. area. I would say there was something wrong with the network you were using if the L3 switches were slower than the L2 switched, flat network Larry Letterman Network Engineer, IT-Lan Cisco Systems David j wrote: >Hello group, I was wondering about the following question: >Is worth to implement VLANs and L3-switching instead a flat L2-network? >I know that this question has been discussed here several times, but the >answer is always the same: depends. What I would like to know is if sombody >has implemented a L3-switched network following the "Cisco style" >(Core-distribution-access or collapsed core-access) and now the performance >is better than with a L2 network. >I had an experience with a network (about 1000 users) with VLANs and Alcatel >L3-switches that was terribly slow when you tried to transfer files between >VLANs so the staff decided migrate to a flat network, that increased the >network performance noticeably. >Do you have real experiences or links talking about real experiences that I >can check? >Thanks and advance. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=58362&t=58350 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: VLANs: To be or not to be [7:58350]
I want to first start out by saying you all know I am not here to bash anyone. But Larry you are right when you say something is wrong with his network and what was wrong with it was the name ALCATEL :). I have experience with the omni core switches and I can say I did not like what I saw in the products. I can go on and on about my experience with them also but I will not bore you all with details. The big problem was power supply failures, the other thing was slowness and the recommended fix from alcatel was always upgrade the software, and most times it would fix it but cause problems with other things. Right before I left the company they did seem to get good code to fix what we were doing. But I will say this because of all the money the company sunk into them we could not get atm to work between a 7500 and one of their switches it went on for 3 months pointing fingers back and forth, then we got all of them in one room Cisco and Alcatel and Cisco came armed with all kinds of docs about how they were following the rfc in their code anyway needless to say the code slinger from alcatel which had to fly over here from india for our meeting ended up having to redo some things to get compatibilty to play with other vendors in the ATM world. I still talk with the other guys I use to work with and they say all those problems are gone now and they are happy with Alcatel. So that is my experience. But I would say with 8500 or 6500 core the CDA model from cisco should give you no problems or SLOWNESS. -Original Message- From: Larry Letterman [mailto:[EMAIL PROTECTED]] Sent: Sunday, December 01, 2002 4:11 AM To: [EMAIL PROTECTED] Subject: Re: VLANs: To be or not to be [7:58350] I have first hand knowledge, we have implemented a core/dist/access network at cisco with L3 at the core and L2 at the acess end. I have also implemented a L3 data center using L3 dist routers and L2 access to the servers. This design, from switch to switch across the L3 dist area, is 1ms or less in the data center and only a couple of ms from most points in the core to most points in the dist. area. I would say there was something wrong with the network you were using if the L3 switches were slower than the L2 switched, flat network Larry Letterman Network Engineer, IT-Lan Cisco Systems David j wrote: >Hello group, I was wondering about the following question: >Is worth to implement VLANs and L3-switching instead a flat L2-network? >I know that this question has been discussed here several times, but >the answer is always the same: depends. What I would like to know is if >sombody has implemented a L3-switched network following the "Cisco >style" (Core-distribution-access or collapsed core-access) and now the >performance is better than with a L2 network. I had an experience with >a network (about 1000 users) with VLANs and Alcatel L3-switches that >was terribly slow when you tried to transfer files between VLANs so the >staff decided migrate to a flat network, that increased the network >performance noticeably. Do you have real experiences or links talking >about real experiences that I can check? >Thanks and advance. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=58376&t=58350 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: VLANs: To be or not to be [7:58350]
Thanks for your answers Larry and Elijah. I also think that there was something wrong with the OmniCore (I didn't work directly with it). I have been also told by a Nortel guy that with their Passport 8600 I wouldn't have any problem (slowness) at all for routing between VLANs, and I belive him, but I want to gather some experiences before implementing L3 switching in other place. Elijah could you say me what version code were you using when you experimented that problems with alcatel? (to compare with our version it would be enough with knowing the year). By the way, we have also experienced some power supply failures... Thanx again, I think I'll definitively recommend to use L3-swithing. Elijah Savage III wrote: > > I want to first start out by saying you all know I am not here > to bash > anyone. But Larry you are right when you say something is wrong > with his > network and what was wrong with it was the name ALCATEL :). I > have > experience with the omni core switches and I can say I did not > like what > I saw in the products. I can go on and on about my experience > with them > also but I will not bore you all with details. The big problem > was power > supply failures, the other thing was slowness and the > recommended fix > from alcatel was always upgrade the software, and most times it > would > fix it but cause problems with other things. Right before I > left the > company they did seem to get good code to fix what we were > doing. But I > will say this because of all the money the company sunk into > them we > could not get atm to work between a 7500 and one of their > switches it > went on for 3 months pointing fingers back and forth, then we > got all of > them in one room Cisco and Alcatel and Cisco came armed with > all kinds > of docs about how they were following the rfc in their code > anyway > needless to say the code slinger from alcatel which had to fly > over here > from india for our meeting ended up having to redo some things > to get > compatibilty to play with other vendors in the ATM world. I > still talk > with the other guys I use to work with and they say all those > problems > are gone now and they are happy with Alcatel. So that is my > experience. > > But I would say with 8500 or 6500 core the CDA model from cisco > should > give you no problems or SLOWNESS. > > -Original Message----- > From: Larry Letterman [mailto:[EMAIL PROTECTED]] > Sent: Sunday, December 01, 2002 4:11 AM > To: [EMAIL PROTECTED] > Subject: Re: VLANs: To be or not to be [7:58350] > > > I have first hand knowledge, we have implemented a > core/dist/access > network at cisco with L3 at the core and L2 at the acess end. > I have > also implemented a L3 data center using L3 dist routers and L2 > access to > the > servers. > > This design, from switch to switch across the L3 dist area, is > 1ms or > less in the data center > and only a couple of ms from most points in the core to most > points in > the dist. area. > > I would say there was something wrong with the network you were > using if > > the L3 switches > were slower than the L2 switched, flat network > > Larry Letterman > Network Engineer, IT-Lan > Cisco Systems > > David j wrote: > > >Hello group, I was wondering about the following question: > >Is worth to implement VLANs and L3-switching instead a flat > L2-network? > > >I know that this question has been discussed here several > times, but > >the answer is always the same: depends. What I would like to > know is if > > >sombody has implemented a L3-switched network following the > "Cisco > >style" (Core-distribution-access or collapsed core-access) and > now the > >performance is better than with a L2 network. I had an > experience with > >a network (about 1000 users) with VLANs and Alcatel > L3-switches that > >was terribly slow when you tried to transfer files between > VLANs so the > > >staff decided migrate to a flat network, that increased the > network > >performance noticeably. Do you have real experiences or links > talking > >about real experiences that I can check? > >Thanks and advance. > > Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=58377&t=58350 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
