Adding an extra switch into our network, it is not going well

[Garacesh]

Okay, so we've recently had two permanent 'temporary' portacabins installed. I've had fibre run from the core switch, got our SFP's, and connected them up, but try as I might I just can't seem to get them to play ball.

 

The switches can see the SFP's and detect them as 10GBASE-SR SFP+ modules, they see the port as active, there's even lights, but.. that's it.

 

Our core switch is a pair of Dell N4032F's

The new switch is a Dell N322P-ON

 

Comparing the new switch to other (non-core) switches, I have:

1. Set up time synchronisation with SNTP (ntp.org) (System/Time Synchronization)
   
2. Given the server an OOB address that can be connected to if that's wired into the rest of the network (System/IP Addressing/Out of Band Interface)
   
3. Set up the DNS and domain name (System/IP Addressing/Domain Name Server and System/IP Addressing/Default Domain Name)
   
4. Enabled the Captive Portal (System/Captive Portal/Global Configuration)
   
5. Ensured the Gi1/0/xx ports are enabled (Switching/Port Configuration)
   
6. Created the same VLAN identifiers, using the same numbers, as the other switches in the network (Switching/VLAN/VLAN Membership)
   
7. Given the fibre link (Te1/0/1) interface the correct PVID of the management VLAN (Switching/VLAN/Port Settings)
   
8. Observed that the Global Default Gateway has correctly automatically set itself to the IP address of the core (Routing/IP/Configuration)
   
9. Given that VLAN a static IP address and subnet mask (Routing/IP/IP Interface Configuration)
   

 

Things I'm confused about:

1. LAG Settings (Switching/VLAN) - There seems to be no rhyme or reason that I can discern as to why these are set and what they are set to across the other switches in the network, but some of them have been set as they're not all on the default Access mode with PVID 1
   
2. What I can only assume is VLAN tagging at the bottom of the VLAN Membership (Switching/VLAN/VLAN Membership) settings. A page full of U's and F's and T's that's just going way over my head, I'll admit it.
   

 

So, I can now get onto the new switch via its IP on the management VLAN instead of the OOB IP, so it looks like traffic can flow between the switch and the rest of the network, but anything you plug into the switch can't identify the network (Windows gives ye olde Unidentified Network) and there's no connection, e.g. you can't log in because there's no DC.

 

Banging my head against the wall here now, doesn't help that the last time I programmed a switch was in Packet Tracer, about 5 years ago...

Edited September 2, 2021 by Garacesh

[Guest Guest]

Have you set your uplink port as a trunk port? If not the process is detailed at

https://www.dell.com/support/kbdoc/en-uk/000104748/how-to-configure-switchport-modes-on-dell-emc-networking-n-series-switches

 

The u t and fs define whether the port is either tagged, untagged or not a member of the VLAN. You need to configure this for each port and VLAN the default I seem to remember is untagged to VLAN 1 which would explain why any devices connected to those ports are unable to communicate.

 

I'm no networking expert but this is how I understand it

 

Hope that makes sense

[Davit2005]

If the switch added is jus doing layer 2 i.e. no routing then you could check to see if you can see and MAC addresses of the clients that are not working on the uplinked switches i.e. the core dell switch. Normally we would do that and it would point to a vlan not tagged on an uplink somewhere just work your way though any switches in the chain and make sure the vlan is tagged/trunked properly.

 

I've no experience with the Dells though, commands or GUI. The principal still is the same just start at the bottom i.e. physical and work your way up through the OSI layers.

 

Have dhcp helper addresses been added to the new vlan?

[Garacesh]

I sussed it out, with a little help from @Boredguy and @localzuk, admittedly. Can't take all the credit!

 

Essentially, I was confused about tagged vs untagged, I was thinking you tag the port as VLAN X to say "Okay, all traffic on this port for VLAN X", which made sense in my head. When in fact, its more like "Packets arriving at this switch will be tagged already, so don't worry about it.".. So in fact, tagged and untagged are the exact opposite of what I thought they were..

 

That, and I was completely overlooking LAG settings on the core switch.

 

So hurrah, mission accomplished, albeit with a significant detour.. Chalk that one up to experience!

[Norphy]

Essentially, I was confused about tagged vs untagged, I was thinking you tag the port as VLAN X to say "Okay, all traffic on this port for VLAN X", which made sense in my head. When in fact, its more like "Packets arriving at this switch will be tagged already, so don't worry about it.".. So in fact, tagged and untagged are the exact opposite of what I thought they were..

 

It took me a while to wrap my head around that one as well. I still occasionally get it the wrong way around when I'm configuring ports on a switch. Glad you got it sorted!

[Davit2005]

I sussed it out, with a little help from @Boredguy and @localzuk, admittedly. Can't take all the credit!

 

Essentially, I was confused about tagged vs untagged, I was thinking you tag the port as VLAN X to say "Okay, all traffic on this port for VLAN X", which made sense in my head. When in fact, its more like "Packets arriving at this switch will be tagged already, so don't worry about it.".. So in fact, tagged and untagged are the exact opposite of what I thought they were..

 

That, and I was completely overlooking LAG settings on the core switch.

 

So hurrah, mission accomplished, albeit with a significant detour.. Chalk that one up to experience!

 

Glad you sorted it. Not helped by different manufacturers using different terminology, lol.

[ADMaster]

I went through that confusion when we retired our Cisco gear.

What helped me was to match the T's

 

Trunk = Tagged.