v9.7 / RHEL; single-partitioned instance

Local connection to db was hanging / taking a long time. Determined that the primary DNS server was down. After making changes to /etc/resolv.conf, connection completed successfully.

Question: Do you know if DB2 needs to perfom hostname resolution for a local connection?

I took a db2 trace and don't really see the functions I expect to see when db2 performs hostname resolution.