How does a L2 dwitch use DNS?

MadJuggla9

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I understand the basics of the question, but even if I wanted to override something locally wouldn't a L2 switch not pay attention?

For instance, all of my ubiquiti gear on the backhaul works no matter what I use. What is a real day situation where this is needed?
 
L2 switch won't use DNS unless the switch itself has a management IP address.
 
I have quite a bit of Ubiquiti equipment, and it has an IP address to change settings/view stats on that's manageable. Can you explain further?
 
meaning it operates on layer 3 is what hes saying. L2 is mac addresses while L3 is IP. if you change an IP then they can communicate but all need to be on the same general subnet. maybe i'm not understanding what your asking but that was my take on it at least.
 
moose is correct.

What am I missing here? How can the DNS fields even work or be of use on an interface level. I understand that it's layer 3 friendly ... but DNS is another ballpark ... and if im wrong i'll regret the confidence I had to say that lol.

I've been thinking very rarely that I should incorporate this 'more' correctly somehow, but then I remind myself that it logically doesn't matter.

I'm curious why it's there really, only useless code if not, poor developers could have had a break instead of adding 2 input fields.
 
What are you referring to? It asking you to put in the DNS servers in the management or being able to access the management by DNS?

Usually having DNS server input fields on network gear is so they can resolve names for things like ping test, firmware updates, etc.

Your questions are poorly worded.
 
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It isnt asking that i do anything to work. It's a 'dumb' switch as I used to call them. I can't think of a use other than a noteworthy placeholder for information about the general network it resides on. You bring up a good point on how it resolves it's name, but like other network equipment on a purely bridges network it reads arp and bridge tables and doesn't need Layer 3.

I apologize about the wording. The concept is very primitive though. I was hoping it may have a use.
 
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Are you talking about it asking for a host name? Do you have a screenshot of what you're referring to?
 
Thats 2 of the many. Like I said, we dont use the DNS. It isnt mandatory
switches.jpg
 
Those look like management settings to me. So, a "dumb switch" like this could use DNS to:

1. check for software updates
2. use for NTP server sync
3. any number of other management related tasks

It wouldn't use any DNS to do anything regarding actually switching traffic.
 
@Arch Hence the reason for the 'smart' switch label I've heard ... makes sense and you're right, I can update it on a layer 3 basis as long as L3 is present. Thank you for the clarification on management,

@/usr/home Apologies for my ignorence on the network definition of managed, i feel like a dumb switch heh.

I still don't know what the DNS area is used for though
 
@4saken ... ikr ...

Ok ... but since I am mistaken, I am going to put working values in, and I want you to answer this: When my APs ON A LAYER 2 BRIDGE request how to get to the head end building or vice versa ... or out to the internet ... who are the APs going to ask at this hop in the network, and depend on, to get to their destination in which the router resides. This is why the question regarding L2 was important L2 was specified on a bridged network.



damn.jpg
 
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The DNS stuff is just for management. You can think of the management interface as a mini server that is logically plugged into the switch.
 
They are going to send to the Gateway that you define. The gateway should have a route out.

Just because they are on a "layer 2 bridge" doesn't mean anything above Layer 2 won't pass. Otherwise there's no point whatsoever.

These are networking basics.
 
The switch only cares about the MAC address. It has 8 physical addresses on its own switch + 1 for management. It learns the MAC address the minute each device on that ports opposite end sends traffic and keeps it for a limited time in its MAC table (instead of using IP's at Layer 3). Using Layer 2 broadcast and ARP all the rest gets solved as far as finding the Layer 3 device which will do the routing.
 
Something no one mentioned. You could have a dynamic IP address on your switch or router and if you have a DNS server and router/switch that supports it your router/switch can update its own DNS entry on the DNS server.
 
Does everyone realize that this switch has a CLI? Within the command line interface, you can use hostnames instead of IP address. The switch needs to be able to resolve DNS within the CLI.
 
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