Oracle 11g seems to ignore your /etc/host.conf i.e It always uses DNS first to try to resolve ip adresses from hostnames. If you remove the nameserver from your configuration and add all servers needed by the database to /etc/host it should run fine.
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When nslookup seems to hang, then your DNS server is down. Just wait about 20 seconds for the next entry in resolv.conf to be tried. If there are 3 DNS servers and all of them are unreachable or not working, then it will take 90 seconds to return. The key here is to tell nslookup what you'd like to do. But before you start, tell nslookup to query a specific DNS server as in:
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When nslookup seems to hang, then your DNS server is down. Just wait about 20 seconds for the next entry in resolv.conf to be tried. If there are 3 DNS servers and all of them are unreachable or not working, then it will take 90 seconds to return. The key here is to tell nslookup what you'd like to do. But before you start, tell nslookup to query a specific DNS server as in:
