I've modified that parameter, now i am using localhost as you said. After that, I ran again "dspace oai import -c" and after a first problem with permissions, it works..
6300 items imported so far...
6400 items imported so far...
6500 items imported so far...
Total: 6579 items
OAI 2.0 manager action ended. It took 314 seconds.

After this, I started again Tomcat but the problem with oai-phm is still there! Any idea?

There's nothing at catalina.out or dspace.log.2013.3.26

De: "helix84" <helix84@centrum.sk>
Para: "Francisco Pais Suarez" <francisco.pais@udc.es>
CC: dspace-tech@lists.sourceforge.net
Enviados: Martes, 26 de Marzo 2013 10:59:01
Asunto: Re: [Dspace-tech] Error with Dspace OAI-PHM listing records and Identifiers

BTW you can change the Solr URL (solr.url) in
[dspace]/config/modules/oai.cfg. Try using "localhost" as the hostname
if you can. Modifications to configuration require Tomcat restart.


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