Directory Server not listening for new connections -- too many fds open.

Issue

• Error messages are found in /var/log/dirsrv/slapd-/errors:

[22/Sep/2009:10:57:49 +0800] - Not listening for new connections - too many fds open
[22/Sep/2009:10:57:49 +0800] - Listening for new connections again

[22/Sep/2009:10:57:49 +0800] - PR_Accept() failed, Netscape Portable Runtime error -5971 (Process open FD table is full.)

• At the same time in the access log:

conn=11408 fd=1022 slot=1022 connection from 10.210.185.13 to 10.210.178.165
conn=11409 fd=1023 slot=1023 connection from 10.210.185.12 to 10.210.178.165
conn=1 fd=64 slot=64 connection from 10.210.185.13 to 10.210.178.165
conn=1 op=-1 fd=64 closed - B1
conn=2 fd=64 slot=64 connection from 10.210.185.12 to 10.210.178.165
conn=2 op=-1 fd=64 closed - B1