Comments on: Gentoo: Easy way to ditch your ISP nameserver http://blog.jolexa.net/2010/01/12/gentoo-easy-way-to-ditch-your-isp-nameserver/ Random thoughts and rants...mostly Linux Mon, 06 Sep 2010 12:28:11 +0000 hourly 1 http://wordpress.org/?v=3.0.1 By: Paul http://blog.jolexa.net/2010/01/12/gentoo-easy-way-to-ditch-your-isp-nameserver/comment-page-1/#comment-1868 Paul Thu, 28 Jan 2010 21:20:31 +0000 http://blog.jolexa.net/?p=619#comment-1868 Thanks for the article, it's exactly what I needed. I had something set up like this previously with djbdns but got lost in a system upgrade and never found the time to do it again. These instructions were nice and easy. To the people who say to use the ISP nameserver: my ISP nameservers are horribly slow and often timeout, they resolve invalid hostames (to point to their ad-infested error page), sometimes resolve valid hostnames as their ad-page as well, and they sell customer's DNS lookup history to companies for targeted advertising. No thanks! Thanks for the article, it’s exactly what I needed. I had something set up like this previously with djbdns but got lost in a system upgrade and never found the time to do it again. These instructions were nice and easy.

To the people who say to use the ISP nameserver: my ISP nameservers are horribly slow and often timeout, they resolve invalid hostames (to point to their ad-infested error page), sometimes resolve valid hostnames as their ad-page as well, and they sell customer’s DNS lookup history to companies for targeted advertising. No thanks!

]]> By: John http://blog.jolexa.net/2010/01/12/gentoo-easy-way-to-ditch-your-isp-nameserver/comment-page-1/#comment-1862 John Mon, 25 Jan 2010 01:43:03 +0000 http://blog.jolexa.net/?p=619#comment-1862 dnsmasq is not just a forwarder; it caches as many external lookups as you configure it to, and it maintains local records (e.g., for local use behind NAT). So it does do its own lookups, both from cache and from local records; if forwards requests for whatever it doesn't have a record of. Also, you do some benchmarking, you'll find that using GoogleDNS is almost never the fastest option, and that using local ISP nameservers is almost always the fastest option. Google's benchmarking app only pays attention to the actual transaction time (the lookup time), and while their centralized servers (and the centralized servers of similar providers, such as opendns) do perform faster lookups, this time reduction is more than offset by the increase in the time it takes for packets to get back and forth between you and their servers. Try is by comparing a few 'time nslookup xxx.xxx.xxx.xxx' operations (being sure to avoid caching artificialities). dnsmasq is not just a forwarder; it caches as many external lookups as you configure it to, and it maintains local records (e.g., for local use behind NAT). So it does do its own lookups, both from cache and from local records; if forwards requests for whatever it doesn’t have a record of.

Also, you do some benchmarking, you’ll find that using GoogleDNS is almost never the fastest option, and that using local ISP nameservers is almost always the fastest option. Google’s benchmarking app only pays attention to the actual transaction time (the lookup time), and while their centralized servers (and the centralized servers of similar providers, such as opendns) do perform faster lookups, this time reduction is more than offset by the increase in the time it takes for packets to get back and forth between you and their servers. Try is by comparing a few ‘time nslookup xxx.xxx.xxx.xxx’ operations (being sure to avoid caching artificialities).

]]> By: Jeremy Olexa http://blog.jolexa.net/2010/01/12/gentoo-easy-way-to-ditch-your-isp-nameserver/comment-page-1/#comment-1854 Jeremy Olexa Wed, 20 Jan 2010 18:52:13 +0000 http://blog.jolexa.net/?p=619#comment-1854 Convince ISPs to get their act together then. Until that happens, I'm going to use something that works... Convince ISPs to get their act together then. Until that happens, I’m going to use something that works…

]]> By: Alex http://blog.jolexa.net/2010/01/12/gentoo-easy-way-to-ditch-your-isp-nameserver/comment-page-1/#comment-1853 Alex Wed, 20 Jan 2010 18:43:49 +0000 http://blog.jolexa.net/?p=619#comment-1853 All well and good, but remember that caching DNS server's are there in your ISP's network for a good reason. If everyone started doing this the extra load on the root servers (See http://www.root-servers.org/) would go up and could adversely impact the service they provide. Granted it would take a fair few networks to do it but the root servers really shouldn't be requested against directly unless need demands it (or you are, for an example, a major ISP). It's all about spreading the load properly around the networks. Note also, that while lookup's after the first request will be quicker (that's a given, it's cached and on your network sub 1ms from your machine in most cases) the first request can, and does at times, take a long time compared to hitting the ISP DNS Cache. Something that isn't mentioned above. Don't forget that many ISP's will also not provide support if you have "non-standard" network setups so you may want to note the old settings for testing if something goes wrong... All well and good, but remember that caching DNS server’s are there in your ISP’s network for a good reason. If everyone started doing this the extra load on the root servers (See http://www.root-servers.org/) would go up and could adversely impact the service they provide. Granted it would take a fair few networks to do it but the root servers really shouldn’t be requested against directly unless need demands it (or you are, for an example, a major ISP).

It’s all about spreading the load properly around the networks.

Note also, that while lookup’s after the first request will be quicker (that’s a given, it’s cached and on your network sub 1ms from your machine in most cases) the first request can, and does at times, take a long time compared to hitting the ISP DNS Cache. Something that isn’t mentioned above.

Don’t forget that many ISP’s will also not provide support if you have “non-standard” network setups so you may want to note the old settings for testing if something goes wrong…

]]> By: Mike Nelson http://blog.jolexa.net/2010/01/12/gentoo-easy-way-to-ditch-your-isp-nameserver/comment-page-1/#comment-1839 Mike Nelson Mon, 18 Jan 2010 15:59:38 +0000 http://blog.jolexa.net/?p=619#comment-1839 Thanks for this, Jeremy. I'm now using unbound locally as well. Those linked articles went a long way in helping me understand DNS better. There has always been a bit of a mystery there for me. Thanks for this, Jeremy. I’m now using unbound locally as well. Those linked articles went a long way in helping me understand DNS better. There has always been a bit of a mystery there for me.

]]> By: Jeremy Olexa http://blog.jolexa.net/2010/01/12/gentoo-easy-way-to-ditch-your-isp-nameserver/comment-page-1/#comment-1835 Jeremy Olexa Fri, 15 Jan 2010 23:19:01 +0000 http://blog.jolexa.net/?p=619#comment-1835 Well, dnsmasq is just a forwarder. So, it is not the one that is doing any lookups. dnsmasq is running on my router as well, it gets it data from a resolver (unbound in my case). Well, dnsmasq is just a forwarder. So, it is not the one that is doing any lookups. dnsmasq is running on my router as well, it gets it data from a resolver (unbound in my case).

]]> By: Yogesh Sharma http://blog.jolexa.net/2010/01/12/gentoo-easy-way-to-ditch-your-isp-nameserver/comment-page-1/#comment-1834 Yogesh Sharma Fri, 15 Jan 2010 23:13:36 +0000 http://blog.jolexa.net/?p=619#comment-1834 I have been using dnsmasq which also provides DHCP to LAN clients along with DNS I have been using dnsmasq which also provides DHCP to LAN clients along with DNS

]]> By: Ivan Yarych http://blog.jolexa.net/2010/01/12/gentoo-easy-way-to-ditch-your-isp-nameserver/comment-page-1/#comment-1833 Ivan Yarych Thu, 14 Jan 2010 14:36:00 +0000 http://blog.jolexa.net/?p=619#comment-1833 Personally I use tinydns' dnscache - works very fast! very reliable! installed in minutes as well. I don't get why use Google's DNS on different continent when you can use your own one near you? :) Personally I use tinydns’ dnscache – works very fast! very reliable! installed in minutes as well.
I don’t get why use Google’s DNS on different continent when you can use your own one near you? :)

]]> By: David http://blog.jolexa.net/2010/01/12/gentoo-easy-way-to-ditch-your-isp-nameserver/comment-page-1/#comment-1828 David Thu, 14 Jan 2010 00:07:09 +0000 http://blog.jolexa.net/?p=619#comment-1828 Thank you, very enlightening content and links. I'd be interested to learn if you have noticed a performance increase (either with your own eyes or with a tool to measure network/DNS performance). Thank you, very enlightening content and links.

I’d be interested to learn if you have noticed a performance increase (either with your own eyes or with a tool to measure network/DNS performance).

]]> By: Stjujsckij Nickolaj http://blog.jolexa.net/2010/01/12/gentoo-easy-way-to-ditch-your-isp-nameserver/comment-page-1/#comment-1823 Stjujsckij Nickolaj Wed, 13 Jan 2010 11:37:42 +0000 http://blog.jolexa.net/?p=619#comment-1823 Another way is to use net-misc/dhcpcd and customize /etc/resolv.conf.{head,tail} files. Another way is to use net-misc/dhcpcd and customize /etc/resolv.conf.{head,tail} files.

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