title: Replicating a read-only solr server
body: <p>I created a solr 1.4 index and would like to serve queries against it for a high-volume application. The index that I am querying is static -- no more updates are allowed. A couple of client apps making requests on the server drive to CPU load to about 200% on a quad-core ubuntu box, so I was thinking of replicating the index on a second box and running it in parallel to allow more throughput.</p>
  
  <p>I shut down solr, copied the index to a separate directory, configured solr server to point to the new index, and fired both of them up. While the original server worked as before, the copy failed to find any documents.</p>
  
  <p>When I do a directory listing on the servers, I see something slightly odd:
  This is the listing of the original index directory</p>
  
  <pre><code>total 3581328
  -rw-r--r-- 1 gene pal 2502676419 2010-07-08 20:53 _38.fdt
  -rw-r--r-- 1 gene pal     488660 2010-07-08 20:53 _38.fdx
  -rw-r--r-- 1 gene pal        198 2010-07-08 20:53 _38.fnm
  -rw-r--r-- 1 gene pal  213752776 2010-07-08 20:54 _38.frq
  -rw-r--r-- 1 gene pal     366496 2010-07-08 20:54 _38.nrm
  -rw-r--r-- 1 gene pal  725677119 2010-07-08 20:54 _38.prx
  -rw-r--r-- 1 gene pal    1124453 2010-07-08 20:54 _38.tii
  -rw-r--r-- 1 gene pal   85260530 2010-07-08 20:54 _38.tis
  -rw-r--r-- 1 gene pal     280471 2010-07-08 20:54 _38.tvd
  -rw-r--r-- 1 gene pal  133020745 2010-07-08 20:54 _38.tvf
  -rw-r--r-- 1 gene pal     977316 2010-07-08 20:54 _38.tvx
  -rw-r--r-- 1 gene pal        299 2010-07-08 20:54 segments_1b
  -rw-r--r-- 1 gene pal         20 2010-07-08 20:54 segments.gen
  </code></pre>
  
  <p>and this is the listing of the copy:</p>
  
  <pre><code>total 3577796
  -rw-r--r-- 1 gene pal 2502676419 2010-07-10 23:16 _38.fdt
  -rw-r--r-- 1 gene pal     488660 2010-07-10 23:15 _38.fdx
  -rw-r--r-- 1 gene pal        198 2010-07-10 23:15 _38.fnm
  -rw-r--r-- 1 gene pal  213752776 2010-07-10 23:15 _38.frq
  -rw-r--r-- 1 gene pal     366496 2010-07-10 23:15 _38.nrm
  -rw-r--r-- 1 gene pal  725677119 2010-07-10 23:16 _38.prx
  -rw-r--r-- 1 gene pal    1124453 2010-07-10 23:16 _38.tii
  -rw-r--r-- 1 gene pal   85260530 2010-07-10 23:15 _38.tis
  -rw-r--r-- 1 gene pal     280471 2010-07-10 23:16 _38.tvd
  -rw-r--r-- 1 gene pal  133020745 2010-07-10 23:16 _38.tvf
  -rw-r--r-- 1 gene pal     977316 2010-07-10 23:16 _38.tvx
  -rw-r--r-- 1 gene pal        299 2010-07-10 23:15 segments_1b
  -rw-r--r-- 1 gene pal         20 2010-07-10 23:15 segments.gen
  </code></pre>
  
  <p>While the file sizes all look the same, the total shown at the top of each listing is different. And even though the solr startup messages suggest that it's looking at this directory</p>
  
  <pre><code>INFO: Opening new SolrCore at solr/, dataDir=./data/
  </code></pre>
  
  <p>admin stats show no documents available to solr</p>
  
  <p>What else should I look at to trouble-shoot this problem?</p>
  
  <p>Thanks,</p>
  
  <p>Gene</p>