This is great @cmr thanks again. I'll get these aggregated for the two EtherChannels (two pairs or two) coming down from the 3750 and we should be good to go.   ... View more

@cmrThat's exactly what is going on! I ran this the other day when researching this and now it makes sense.   Number of channel-groups in use: 3 Number of aggregators: 3 Group Port-channel Protocol Ports ------+-------------+-----------+----------------------------------------------- 1 Po1(SU) LACP Te1/1/1(P) Te2/1/1(P) 3 Po3(SU) LACP Te3/1/1(P) Te5/1/1(P) 4 Po4(SU) LACP Te3/1/2(P) Te4/1/2(P)   Channel 3 is two links coming down from the 3750's to two of the 2960's in their own stack. So it sounds like as long as I get both SFP's from the existing 2960 stacks moved down to the MS225 then the SFP's on the 3750's will enable and allow that traffic. Thanks so much for the help! ... View more

@cmr  My apologies but I'm not clear (my lack of knowledge) on why we would not have the 3750 stack and the MS225 stack connected. Currently, the 3750 stack and the 2960 stack are connected with fiber links through these SFP's. My understanding was this was for redundant connections between the stacks and faster links for any traffic between the stacks. Would the MS225 stack not also be connected the same way to the 3750 stack? Thanks ... View more

@cmrThere is an entry for the channel group 3, I'll put it below but it looks to be the same as the actual port. interface Port-channel3 description PortChannel to Mezz Switches switchport trunk encapsulation dot1q switchport mode trunk   As far as cables, the local tech wanted to hook this stack up to the core and put a couple of cables over from the 2960 into the stack to test and make sure everything was ok before we completely removed the (4) 2960's. When I first hooked everything up I got the MS225's in the stack, put one ethernet cable from the core in to get the stack on the internet and upgraded the firmware and did all the setup. I then pulled the SFP from one of the 2960's that I freed up and was going to get that connection as the main link between the core and MS225's then one that communication was working I was going to start moving a handful of workstations over to the MS225 and make sure all was well there. When you say "you don't want that line" are you taking about the SFP connection or the ethernet back to the other Cisco switches? Thanks for your help. ... View more

Thanks for the info. It appears to be the same model number as the one that I moved from to 2960 to MS225, SFP-10GBase-SR. ... View more

@GIdenJoe  I haven't looked specifically at the SFP in the 3750 but I'm pretty sure all of these SFP were Cisco branded 10G SFPs. Researching this I did find where I could not set the speed or duplex for the SFP which is why I found it strange that the Meraki gave the 1G options. When we had this core (3750's) and these 2960's installed a couple of years ago it was an all Cisco install and if I plug this SFP back into the 2960 I'm replacing it comes back online but when I put it in the Meraki, the Meraki shows it connected but the 3750 shows it as disconnected or actually "line protocol is down (suspended)". It's possible that there is a setting on the 3750 port that's causing this but according to the MSP we got these from, they went through the configs and said everything seemed ok. I checked the MS225 that the SFP is plugged into and it is showing as a 10.3 Gbps Cisco SFP-10G-SR and all three switches of the stack are MS225's. Thanks for your help. ... View more

@cmrWe are using a Cisco branded SFP and I did find it as a Meraki supported SFP. It appears that both sides are set to trunk mode and VLAN1 with all VLANs allowed. While I do some networking I'm more of a generalist since I have to support many different things and normally call in an expert once it goes above my head or I can't find any answer online. That being said I can't say for sure but I just pulled this from the config if that will help answer this question.   interface TenGigabitEthernet5/1/1 switchport trunk encapsulation dot1q switchport mode trunk channel-group 3 mode active   As for EOL, yeah, these MS225s are replacing the 2960's that were EOL last year and once we get these going we replace the 3750's next year. Thanks for your help. ... View more

Thanks for the quick responses.   Yes, the MS225's are in a stack. Three MS225-48-FP all connected with stacking cables. Currently, I have one ethernet cable connected to the core for internet connectivity but if I unplug that there is no internet connection for these devices. The SFP is in port 49 of one of the switches and I have tried the SFP port on another of the MS225's. The SFP module shows as a Cisco SFP device at 10.3 Gbps so that appears to be correct. On the core, it appears that it is hard-set Full Duplex and I found a Cisco support page that said that 10G ports do not support speed or duplex features and only operate at 10,000Mb/s and in full-duplex mode. ... View more