How do I prevent unwanted DNS lookups on a Cisco switch?

How do I disable DNS lookup configuration?

How do I disable the DHCP discovery of DNS on my device?

I have a device with no network interface card that is connecting to the network via WAN. The only IP address I have is from DHCP. I want to avoid using DNS from the network because it doesn't seem to provide me much functionality in doing basic things like updating my email, changing websites etc.

I'm running Mac OS X Snow Leopard and using an Ethernet card, but my wireless NIC is broken. I tried to just uninstall resolvconf, but when I run dpkg-reconfigure resolvconf, I am told that resolvconf is not configured. (The answer to this question seems to make sense to me, but I'm still getting the warning).

How do I disable the DHCP lookup? Try editing /etc/dnsmasq.conf and putting all but one of the lines in here blank: # See for more info on using this config file. Bind-interfaces. # Do not include your domain server. Bogus-authoritative. Server=/pool.ntp.org/zone
Server=/pool.org/0.ubuntu.org
# Do not forward addresses. Dhcp-range=address,192.168.2,192.6,255.0
# Do not forward addy with broadcast and subnetmask. Dhcp-range=address,192.2,255.0
Replace address,192.2 with your specific IP address and 192.2/255.0 with your gateway.

How to reduce DNS traffic?

While this may seem to be an obvious answer, I see people doing the same thing all over the place.

A lot of them even link that as a fix (see below).

Do the same thing for yourself. That is, don't do DNS lookups with recursive resolvers. Use a local DNS cache instead. You can easily set
up zone files on your server or on a local caching system that will. automatically cache the records you specify. Is there some kind of DNS trickery that I'm missing? Is this something that should be happening on the client? It's not really DNS, it's HTTP. If you make sure to use a local caching DNS resolver for local requests, then make sure it's properly cached, then you should see a significant reduction in connection timeouts.

How do I reduce the number of DNS lookups?

My application needs to be able to reach external web sites without requiring a DNS lookup.

The DNS server is hosted at the local network (it's a PC). ? Or should I look for a different approach? One thing you could do is setup your DNS server to cache DNS lookups, that way when the client makes a request for example.com it will also ask the DNS server if it's present in the cache and if it is return the resolved address from the cache.

You would need to ensure your DNS server is configured for this, it can usually be found under DNS-Setup on the Options tab. The same thing could be done using other methods of DNS resolvers, not just the DNS servers that your OS installs, but there are other options out there as well.

How do I prevent unwanted DNS lookups on a Cisco switch?

(specifically, how do I not have DNS lookups when using telnet?).

Do you really want to not even see anything after the IP address in the Telnet connection? You may use a Cisco device that is configured for a CLI (cubic) network without routing with some basic features enabled. This will give you a CLI connection with no routing so it can be considered similar to an old fashion serial connection.

I've used this with Cisco devices, mostly 3050, 2960, 2921 series routers. For the most part, if there is a configuration change, I usually get the message with a few seconds notice. If I need a complete reboot the message will sometimes indicate that.

It really has to do with the configuration. If you have routing enabled by default there are a lot of options to hide the messages, but not everything can be configured due to restrictions. The Cisco device will keep track of all configuration changes (a bit of a pain), it just depends how they track the changes and what type of information you wish to hide from users.