Installing and Administering Internet Services

114 Chapter 3
Configuring and Administering the BIND Name Service
Troubleshooting the BIND Name Server
OK answers is the number of responses to queries that contain some
information.
FAIL answers is the number of responses indicating either that the
name does not exist or that there is no data of the requested type for this
name.
FORMERR answers is the number of malformed response packets from
other name servers. A message is sent to the syslog daemon listing the
sender of the malformed response packet.
system queries are queries generated by the name server. These
usually occur when the name server detects another name server listed
for a domain for which there is no address data. The system query is an
attempt to find the address data for that name server. System queries
are also used to keep up-to-date information about the name servers for
the root domain.
prime cache calls are calls to update the information about the
name servers for the root domain.
check_ns calls are calls to check the state of the information about
the name servers for the root domain.
bad responses dropped are responses from remote name servers that
are dropped. These occur most often when the remote name server
responds with SERVFAIL, indicating a problem with the server’s domain
data.
martian responses are responses from unexpected addresses. The
name server keeps track of how long it takes for a remote name server to
respond. If the remote name server is a multi-homed host, a query to one
of the addresses may result in a response from another of its addresses.
If the local server does not know about this other address, the response is
counted as a martian response.
unknown query types are queries for data types unknown to this
server.
A queries are queries for the host address for a domain name. The
gethostbyname library routine generates these address queries.
CNAME queries are queries for the canonical name for a domain name.
Some versions of sendmail query for CNAME records during name
canonicalization from $[ $] tokens in
/var/adm/sendmail/sendmail.cf.