Where are local hostnames resolved with no DNS server ?

Soldato
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My home setup is "fairly" simple.
I have an Asus RT-N56U router behind a BT modem handing out IPs via DHCP.
and no dedicated DNS server.

I have just finished upgrading my nas4free server to new hardware, at this moment in time both servers are up and running and if i ping nas4free it pings the old server, despite me changing the name to oldnas

I have given the oldnas several new IPs and when i ping nas4free it still finds the old server with its new IP instead of the new one.
advanced ipscanner shows both machines with nas4free as the hostname.
pinging the ip address directly does work so the new NAS is workin properly.

what I want to know is where is this information stored so that I can flush it? There is nothing in the router that I can see.

Currently windows shares and network drives are all aiming themselves at the old NAS due to me using the hostname instead of the direct IP.
 
Soldato
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@bledd
I had already tried rebooting pc/router/NAS
And the router isn't really a DNS server as such, its just hands any DNS requests over to a "proper" DNS server.
I have scoured the settings and cannot find any kind of cache or list of DNS addresses stored on it.

have just tried the flushdns as above but its still resolving nas4free as the ip from the old machine. and advanced ip scanner still shows both machines as nas4free.
 
Associate
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Hosts file?

Or if in the same domain, it could be resolving it with a broadcast?

Or is the local router responding with a name attached to a DHCP reservation?
 
Soldato
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Hosts file?

Or if in the same domain, it could be resolving it with a broadcast?

Or is the local router responding with a name attached to a DHCP reservation?
hosts file is clean (this is happening on 2 machines)
I don't have a "domain" as such, but how does the broadcast work ?
There is no DCHP reservation for the old NAS only for the new one.

if i do a ping -a on the new NAS it does list the correct hostname
but also lists the same hostname on the old server as nas4free using that same command.


Externally yes, but your router is most likely doing your local dns. Normally hand in hand with dhcp.

How could I find out ?, there is nothing in the routers log at present, perhaps there is some sort of command I can use that would help me trace this ?




[EDIT]
Should mention that if I ping "oldnas" I get a
Ping request could not find host oldnas. Please check the name and try again.
 
Associate
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Welcome to the weird and wonderful world of Microsoft NETBIOS (aka CIFS) where any fileshare that starts up will normally broadcast locally to say "I'm here!" which then can confuse the hell out of name resolution for normal TCP-IP.

Glad you sorted it anyhow.
 
Soldato
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I didn't actually fully sort it.

only 1 pc on the network was able to successfully ping NETBIOS names.
I've just use IP addresses to setup network shares and Kodi now.
 
Soldato
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You need to clear your DNS cache on your laptop/desktop DNS cache on your router, BT modem is going to be your sticking point but the router is handling the internal DNS. Make sure the DNS setting (LAN > DHCP Server) in your DHCP settings on the router are left blank, or point to the routers IP address, not Google (8.8.8.8) or anything else.
 
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