client
Processing of client requests.
cname
Nameservers that are skipped due to them being a CNAME rather than A / AAAA records.
config
Configuration file parsing and processing.
database
Messages relating to the databases used internally by the name server to store zone and cache data.
default
Logging options for those categories where no specific configuration has been defined.
delegation-only
Queries that have been forced to NXDOMAIN as the result of a delegation-only zone or a delegation-only in a forward, hint, or stub zone declaration.
dispatch
Dispatching of incoming packets to the server modules where they are to be processed.
dnssec
DNSSEC and TSIG protocol processing.
dnstap
The “dnstap” DNS traffic capture system.
edns-disabled

Log queries that have been forced to use plain DNS due to timeouts. This is often due to the remote servers not being RFC 1034-compliant (not always returning FORMERR or similar to EDNS queries and other extensions to the DNS when they are not understood). In other words, this is targeted at servers that fail to respond to DNS queries that they don’t understand.

Note: the log message can also be due to packet loss. Before reporting servers for non-RFC 1034 compliance they should be re-tested to determine the nature of the non-compliance. This testing should prevent or reduce the number of false-positive reports.

Note: eventually named will have to stop treating such timeouts as due to RFC 1034 non-compliance and start treating it as plain packet loss. Falsely classifying packet loss as due to RFC 1034 non-compliance impacts DNSSEC validation, which requires EDNS for the DNSSEC records to be returned.

general
Catch-all for many things that still are not classified into categories.
lame-servers
Misconfigurations in remote servers, discovered by BIND 9 when trying to query those servers during resolution.
network
Network operations.
notify
The NOTIFY protocol.
nsid
NSID options received from upstream servers.
queries

Location where queries should be logged.

At startup, specifying the category queries also enables query logging unless the querylog option has been specified.

The query log entry first reports a client object identifier in @0x<hexadecimal-number> format. Next, it reports the client’s IP address and port number, and the query name, class, and type. Next, it reports whether the Recursion Desired flag was set (+ if set, - if not set), whether the query was signed (S), whether EDNS was in use along with the EDNS version number (E(#)), whether TCP was used (T), whether DO (DNSSEC Ok) was set (D), whether CD (Checking Disabled) was set (C), whether a valid DNS Server COOKIE was received (V), and whether a DNS COOKIE option without a valid Server COOKIE was present (K). After this, the destination address the query was sent to is reported. Finally, if any CLIENT-SUBNET option was present in the client query, it is included in square brackets in the format [ECS address/source/scope].

client 127.0.0.1#62536 (www.example.com): query: www.example.com IN AAAA +SE client ::1#62537 (www.example.net): query: www.example.net IN AAAA -SE

(The first part of this log message, showing the client address/port number and query name, is repeated in all subsequent log messages related to the same query.)

query-errors
Information about queries that resulted in some failure.
rate-limit

Start, periodic, and final notices of the rate limiting of a stream of responses that are logged at info severity in this category. These messages include a hash value of the domain name of the response and the name itself, except when there is insufficient memory to record the name for the final notice. The final notice is normally delayed until about one minute after rate limiting stops. A lack of memory can hurry the final notice, which is indicated by an initial asterisk (*). Various internal events are logged at debug 1 level and higher.

Rate limiting of individual requests is logged in the query-errors category.

resolver
DNS resolution, such as the recursive lookups performed on behalf of clients by a caching name server.
rpz
Information about errors in response policy zone files, rewritten responses, and, at the highest debug levels, mere rewriting attempts.
security
Approval and denial of requests.
serve-stale
Indication of whether a stale answer is used following a resolver failure.
spill
Queries that have been terminated, either by dropping or responding with SERVFAIL, as a result of a fetchlimit quota being exceeded.
trust-anchor-telemetry
Trust-anchor-telemetry requests received by named.
unmatched
Messages that named was unable to determine the class of, or for which there was no matching view. A one-line summary is also logged to the client category. This category is best sent to a file or stderr; by default it is sent to the null channel.
update
Dynamic updates.
update-security
Approval and denial of update requests.
xfer-in
Zone transfers the server is receiving.
xfer-out
Zone transfers the server is sending.
zoneload
Loading of zones and creation of automatic empty zones.