"No Route To Host"/"Destination Unreachable" Cisco Nexus N9K

I have cloned my N5K settings for vlan and routing to the best of my abilities, but I am stuck on the static routes. I believe this is because the main difference is that the N5K connects directly to the RB5009 router, and the N9K connects to the N5K. If I remove the routes I have configured I get “no route to host” When I apply those routes, I get “destination host unreachable”. Any advice? I have also copied the vlan settings to the new vlan in winbox for the Mikrotik router. Lan_10G is working on N5K, where as LAN_25G is on the N9K and is not working.



switches connect to switches VIA trunk ports OR Routed interfaces. not both. (well, usually.)

if all you need to do is get traffic from the tail end to the router (it looks like that is all you need to do) then your switches should use trunk ports to connect up stream, and the router at the end is where you manage traffic.

a switch and a VLAN do not need any IP addresses assigned to them unless they are routing, (you do not need to route until traffic gets to your mikrotick it looks like.)

you are currently kind-of trying to route VLANS to the Mikrotik.

I’m just trying to get the different VLANs 100 (will be renamed 10 soon), 200 (20 soon), and 30 to be able to talk to each other and the internet. I followed the same configuration I used for Nexus 5596UP, but I must be missing something with this Nexus C92160YC-X. Removing the routing and having eth1/1 as a trunk with no VLAN besides the default VLAN 1 (shutdown) gives me a response of “no route to host”.

a trunk port has a untagged vlan (1 would be fine) and then tagging placed on all VLANs that need to pass through. so VLAN 1 untagged, VLAN 10, 20, 30, Tagged , and your router would need a trunk port and router addresses to receive them.

Cisco devices ‘assume’ the first 4094 vlans passed 1 are all tagged by default. but the Mikrotik would need you to tag them.

this is all assuming you are trying to build a switched network.

a routed network you could do untagged ports for each VLAN and hand them up to the router individually if that is what you were thinking?

I’m still learning all of this ahead of testing for my CCNA, so I don’t know what I am thinking. I assume routed is how I set up the N5K as it is now. I am trying to plan out my network destroy it and start from scratch, but I want to make sure I know how to get it to work afterwards, as my parent’s internet is partially reliant on it. As is my home assistant setup. Would a switched network be the better one for my use case of a homelab/home office, isolated IoT, guest WiFi, standard WiFi, etc…?

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Here is what I have done thus far. Aside from setting the clock and upgrading nxos from 7.0(3)I7(3) to 9.3(10) (following the proper upgrade path as laid out by Cisco: 7.0(3)I7(3) → 7.0(3)I7(8) → 9.3(6) → 9.3(10)). I do not know how I will assign these VLANs yet, as I am reworking my network design/layout/topology (?), but I threw them in there for now with no configuration.



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I have run out of ideas, and do not know where to go from here. :frowning:

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sorry, i had a busy weekend.

could you show your physical topology somehow? it would be easier for me to help with routed vs switched if i know what the paths look like.

No worries, I get it! Life be like that sometimes! :smiley: I got help from a discord server and the current state of things is: the switch is up and connected, I am on a PC that is connected to it and it has internet, this test machine can ping and be pinged by the switches and router, but they cannot traceroute each other. This test PC cannot be pinged by any other device on the network besides those, though it can ping them. I also need to figure out intervlan routing on both of my cisco switches (N9K-C92160YC-X and N5K-5596UP). The routing is especially significant for the N9K as it is bottlenecked by both the N5K and RB5009 10Gbe uplinks.

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depending on the service you may need to use ‘IP-helper’ addresses. you probably do need to build out V-LAN routes as part of your CCNA stuff, but MOST of the time in production, using a V-LAN router is the last possible solution for a network connection. Also, make sure you complete at least one build of a switched network with a mixed set of equipment brands so you can understand trunk ports.

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I don’t understand the difference you mean between routed and switched networks. Is my current network topology what you would call routed.

Mikrotik RB5009
N5K-C5596UP
N9K-C92160YC-X

We’re looking to trunk VLAN 10 (192.168.10.0/24) across all three devices such that:

RB5009 owns 192.168.10.1
N5K owns 192.168.10.2
N9K owns 192.168.10.3

If so, I do not know what you mean by switched network, or where to begin configuring one.

if you built this network and the ONLY place on your network that contains ACLs or route entries is on the device marked ROUTER, you have a SWITCHED network.

if you built this network and used ACLs or static routes on the 2 devices marked “SWITCH” to get traffic to the ROUTER, you have a ROUTED network.

a layer 3 switch can have traffic work on it normally with multiple VLANS assigned to multiple ports on it and the switch itself and none of the VLANS on it even need a IP assigned at all. usually i will assign a management IP to the switch, but it is unnecessary for traffic flow.

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Ah, okay, I understand now. So then, yes, my setup is routed. The two Nexus switches would not connect otherwise. They are both layer 2 devices. From what I recall, the N5K is only a lay2 device. I have a layer 3 add on module for it, but have not been able to get it to work. As for the N9K, not knowing otherwise, I chose to configure it as layer 2 during initial guided setup which is what was labeled as the default configuration for the device. Are you saying that I need to erase the current config and start over with the ports configured for layer 3?

Layer 2 devices usually do not alloy routing at all, or have very limited routing tables available. along with usually only having no, or limited VLAN support.

Layer 3 devices are usually where ‘routing’ capabilities start, but also fully fleshed out VLAN and TRUNK support is baked in.

i HATE the nexus switches with a passion and will not get into how to make them ‘work’.

honestly all of my networks have been built to standards that are supported by most manufactures. Cisco has a hard time working with other Cisco devices, let alone network standards. Before i go off on a tangent, i am unable to give guidance productively for Nexus devices.

Understood, no worries, and thanks anyway.