title: Where is the DNS cache stored for Ubuntu?
body: <p>Where can I find the actual DNS cache storage on a Ubuntu file system?</p>
  
  <p>I have a PHP script which uses libcurl to crawl several hundred pages on the same domain, and I have it set to use a global DNS cache, and set the DNS cache timeout to 5 minutes (300 seconds), which definitely speeds things up, because a few of the calls were hanging due to name resolution issues (too many name resolution requests for the same domain, the server must have been rejecting/hanging on some).</p>
  
  <p>Another question I had is, is it possible to have a permanent storage place for domain to IP address mappings, so that you don't even have to use DNS caching in libcurl?  can I use /etc/resolv.conf to store an external domain name and map it to it's IP address, would this work?</p>
  
  <p>I've been in in web development for awhile now so I'm pretty familiar with the linux command line and messing with configurations/settings but I haven't been able to find an answer to this question</p>
  
  <p>I guess I could just make the actual libcurl requests use the IP address of the websites I'm pulling from, but I'd rather have it use the domain name for logging purposes so that I can monitor for any issues with requests hanging</p>