#Are we using Layer 2 or Layer 3 network?

1 messages · Page 1 of 1 (latest)

inner shard
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My understanding is broadcast domain divides ONTAP networks as Layer 2 network, which means when I run "broadcast domain show", the networks show me there are all layer 2 networks, 128.58.40.0/24 in this case. "net int show -vserver" shows me networks and data interfaces for clients to connect to the cluster, 128.58.40.x/24. As you can see below, both commands in my case show me the same network.

So, my question is for the data network, are we really using the layer 2 or layer 3 network? If the answer is the layer 2 network, then it shouldn't be routable. But, in fact, on the NFS client using the interface 128.59.40.x to mount NFS has no such NIC configured for the network, which means the client is using routable network to connect to the cluster.

Hopefully, some experts here can help me out.

leaden basalt
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I'm not sure I understand the question. If you have a default route in your SVM (and your NFS client), then you're obviously using a Layer 3 routed network. If you don't have a default gateway set, then you're restricted to the layer 2 network. If your clients can connect from a different subnet, then there is routing involved

inner shard
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You are correct, and I can understand what you said. As I said, the same subnet "128.58.40.x/24" as a broadcast domain and also as the network for "vserver1". "A broadcast domain in clustered Data ONTAP is a layer 2 object that allows the logical division of resources in a clustered Data ONTAP system.", excerpted from https://www.netapp.com/media/16885-tr-4182.pdf, section 3.2. My question was how to explain the same network showed up in both "broadcast domain show" and in "net int -vserver vserver1 show".

The MTU size for the network as shown along with the broadcast domain is 9000. Does that mean the vserver's network can allow to use MTU size 9000? This is another question of mine.

hearty flare
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what the broadcast domain is called is something you can determine yourself. I find it useful to use some indication to the vlan in use

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the mtu will be valid for the interfaces in the broadcast domain. You need to make sure all of the clients can use jumbo frames of you are going to use them on the netapp side... and that alle the switches between the netapp and the clients are also configured to use jumbo frames

leaden basalt
inner shard
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I can understand the domain name could be anything, my question was not on that. If you look at the all ports listed from both commands, they showed the same port list, that is my question about (I didn't make myself clear). This made me wondering if we are using Layer 2 since broadcast-domain show only list layer 2's ports, and vserver uses the same ports. I also understand we may very well be using Layer3 only by the fact that we are using routing to get NFS. But, I just need help to explain the confusion.

@leaden basalt , the vserver also uses 128.58.40.x/24 network and ports. 10.192.27.49/24 was not a question.

leaden basalt
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You are "using Layer 3" if you have a default gateway and/or network or host routes. You have not shown us the output of network route show so we cannot tell you if your network is routed or flat. The IP addresses themselves don't tell you that.
It's the same as on any regular windows PC: you set up an IP address to talk to other devices on your local network segment (coincidentally also called "broadcast domain"). As soon as you configure a default gateway, you can communicate with hosts outside your layer 2 broadcast domain. It works the exact same way on ONTAP

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as for "showing the same ports": you see the port your LIF is currently hosted on, because that is helpful for many things (like troubleshooting). But actually you wouldn't even need to see this in the net int show output, because it doesn't matter: all that matters is the broadcast domain. (The fact that you still have to specify a port when creating a LIF is a leftover from when Broadcast Domains didn't exist)