
This is a summary of the named.conf options supported by
this version of BIND 9.

acl <string> { <address_match_element>; ... }; // may occur multiple times

controls {
        inet ( <ipv4_address> | <ipv6_address> |
            * ) [ port ( <integer> | * ) ] allow
            { <address_match_element>; ... } [
            keys { <string>; ... } ] [ read-only
            <boolean> ]; // may occur multiple times
        unix <quoted_string> perm <integer>
            owner <integer> group <integer> [
            keys { <string>; ... } ] [ read-only
            <boolean> ]; // may occur multiple times
}; // may occur multiple times

dlz <string> {
        database <string>;
        search <boolean>;
}; // may occur multiple times

dnssec-policy <string> {
        dnskey-ttl <duration>;
        keys { ( csk | ksk | zsk ) ( key-directory ) lifetime <duration>
            algorithm <integer> [ <integer> ]; ... };
        parent-ds-ttl <duration>;
        parent-propagation-delay <duration>;
        parent-registration-delay <duration>;
        publish-safety <duration>;
        retire-safety <duration>;
        signatures-refresh <duration>;
        signatures-validity <duration>;
        signatures-validity-dnskey <duration>;
        zone-max-ttl <duration>;
        zone-propagation-delay <duration>;
}; // may occur multiple times

dyndb <string> <quoted_string> {
    <unspecified-text> }; // may occur multiple times

key <string> {
        algorithm <string>;
        secret <string>;
}; // may occur multiple times

logging {
        category <string> { <string>; ... }; // may occur multiple times
        channel <string> {
                buffered <boolean>;
                file <quoted_string> [ versions ( unlimited | <integer> ) ]
                    [ size <size> ] [ suffix ( increment | timestamp ) ];
                null;
                print-category <boolean>;
                print-severity <boolean>;
                print-time ( iso8601 | iso8601-utc | local | <boolean> );
                severity <log_severity>;
                stderr;
                syslog [ <syslog_facility> ];
        }; // may occur multiple times
};

lwres { <unspecified-text> }; // obsolete, may occur multiple times

managed-keys { <string> ( static-key
    | initial-key | static-ds |
    initial-ds ) <integer> <integer>
    <integer> <quoted_string>; ... }; // may occur multiple times, deprecated

masters <string> [ port <integer> ] [ dscp
    <integer> ] { ( <masters> | <ipv4_address> [
    port <integer> ] | <ipv6_address> [ port
    <integer> ] ) [ key <string> ]; ... }; // may occur multiple times

options {
        acache-cleaning-interval <integer>; // obsolete
        acache-enable <boolean>; // obsolete
        additional-from-auth <boolean>; // obsolete
        additional-from-cache <boolean>; // obsolete
        allow-new-zones <boolean>;
        allow-notify { <address_match_element>; ... };
        allow-query { <address_match_element>; ... };
        allow-query-cache { <address_match_element>; ... };
        allow-query-cache-on { <address_match_element>; ... };
        allow-query-on { <address_match_element>; ... };
        allow-recursion { <address_match_element>; ... };
        allow-recursion-on { <address_match_element>; ... };
        allow-transfer { <address_match_element>; ... };
        allow-update { <address_match_element>; ... };
        allow-update-forwarding { <address_match_element>; ... };
        allow-v6-synthesis { <address_match_element>; ... }; // obsolete
        also-notify [ port <integer> ] [ dscp <integer> ] { ( <masters> |
            <ipv4_address> [ port <integer> ] | <ipv6_address> [ port
            <integer> ] ) [ key <string> ]; ... };
        alt-transfer-source ( <ipv4_address> | * ) [ port ( <integer> | * )
            ] [ dscp <integer> ];
        alt-transfer-source-v6 ( <ipv6_address> | * ) [ port ( <integer> |
            * ) ] [ dscp <integer> ];
        answer-cookie <boolean>;
        attach-cache <string>;
        auth-nxdomain <boolean>; // default changed
        auto-dnssec ( allow | maintain | off );
        automatic-interface-scan <boolean>;
        avoid-v4-udp-ports { <portrange>; ... };
        avoid-v6-udp-ports { <portrange>; ... };
        bindkeys-file <quoted_string>;
        blackhole { <address_match_element>; ... };
        cache-file <quoted_string>;
        catalog-zones { zone <string> [ default-masters [ port <integer> ]
            [ dscp <integer> ] { ( <masters> | <ipv4_address> [ port
            <integer> ] | <ipv6_address> [ port <integer> ] ) [ key
            <string> ]; ... } ] [ zone-directory <quoted_string> ] [
            in-memory <boolean> ] [ min-update-interval <duration> ]; ... };
        check-dup-records ( fail | warn | ignore );
        check-integrity <boolean>;
        check-mx ( fail | warn | ignore );
        check-mx-cname ( fail | warn | ignore );
        check-names ( primary | master |
            secondary | slave | response ) (
            fail | warn | ignore ); // may occur multiple times
        check-sibling <boolean>;
        check-spf ( warn | ignore );
        check-srv-cname ( fail | warn | ignore );
        check-wildcard <boolean>;
        cleaning-interval <integer>; // obsolete
        clients-per-query <integer>;
        cookie-algorithm ( aes | siphash24 );
        cookie-secret <string>; // may occur multiple times
        coresize ( default | unlimited | <sizeval> );
        datasize ( default | unlimited | <sizeval> );
        deallocate-on-exit <boolean>; // ancient
        deny-answer-addresses { <address_match_element>; ... } [
            except-from { <string>; ... } ];
        deny-answer-aliases { <string>; ... } [ except-from { <string>; ...
            } ];
        dialup ( notify | notify-passive | passive | refresh | <boolean> );
        directory <quoted_string>;
        disable-algorithms <string> { <string>;
            ... }; // may occur multiple times
        disable-ds-digests <string> { <string>;
            ... }; // may occur multiple times
        disable-empty-zone <string>; // may occur multiple times
        dns64 <netprefix> {
                break-dnssec <boolean>;
                clients { <address_match_element>; ... };
                exclude { <address_match_element>; ... };
                mapped { <address_match_element>; ... };
                recursive-only <boolean>;
                suffix <ipv6_address>;
        }; // may occur multiple times
        dns64-contact <string>;
        dns64-server <string>;
        dnskey-sig-validity <integer>;
        dnsrps-enable <boolean>; // not configured
        dnsrps-options { <unspecified-text> }; // not configured
        dnssec-accept-expired <boolean>;
        dnssec-dnskey-kskonly <boolean>;
        dnssec-enable <boolean>; // obsolete
        dnssec-loadkeys-interval <integer>;
        dnssec-lookaside ( <string>
            trust-anchor <string> |
            auto | no ); // obsolete, may occur multiple times
        dnssec-must-be-secure <string> <boolean>; // may occur multiple times
        dnssec-policy <string>;
        dnssec-secure-to-insecure <boolean>;
        dnssec-update-mode ( maintain | no-resign );
        dnssec-validation ( yes | no | auto );
        dnstap { ( all | auth | client | forwarder |
            resolver | update ) [ ( query | response ) ];
            ... }; // not configured
        dnstap-identity ( <quoted_string> | none |
            hostname ); // not configured
        dnstap-output ( file | unix ) <quoted_string> [
            size ( unlimited | <size> ) ] [ versions (
            unlimited | <integer> ) ] [ suffix ( increment
            | timestamp ) ]; // not configured
        dnstap-version ( <quoted_string> | none ); // not configured
        dscp <integer>;
        dual-stack-servers [ port <integer> ] { ( <quoted_string> [ port
            <integer> ] [ dscp <integer> ] | <ipv4_address> [ port
            <integer> ] [ dscp <integer> ] | <ipv6_address> [ port
            <integer> ] [ dscp <integer> ] ); ... };
        dump-file <quoted_string>;
        edns-udp-size <integer>;
        empty-contact <string>;
        empty-server <string>;
        empty-zones-enable <boolean>;
        fake-iquery <boolean>; // ancient
        fetch-glue <boolean>; // ancient
        fetch-quota-params <integer> <fixedpoint> <fixedpoint> <fixedpoint>;
        fetches-per-server <integer> [ ( drop | fail ) ];
        fetches-per-zone <integer> [ ( drop | fail ) ];
        files ( default | unlimited | <sizeval> );
        filter-aaaa { <address_match_element>; ... }; // obsolete
        filter-aaaa-on-v4 <boolean>; // obsolete
        filter-aaaa-on-v6 <boolean>; // obsolete
        flush-zones-on-shutdown <boolean>;
        forward ( first | only );
        forwarders [ port <integer> ] [ dscp <integer> ] { ( <ipv4_address>
            | <ipv6_address> ) [ port <integer> ] [ dscp <integer> ]; ... };
        fstrm-set-buffer-hint <integer>; // not configured
        fstrm-set-flush-timeout <integer>; // not configured
        fstrm-set-input-queue-size <integer>; // not configured
        fstrm-set-output-notify-threshold <integer>; // not configured
        fstrm-set-output-queue-model ( mpsc | spsc ); // not configured
        fstrm-set-output-queue-size <integer>; // not configured
        fstrm-set-reopen-interval <duration>; // not configured
        geoip-directory ( <quoted_string> | none ); // not configured
        geoip-use-ecs <boolean>; // obsolete
        glue-cache <boolean>;
        has-old-clients <boolean>; // ancient
        heartbeat-interval <integer>;
        host-statistics <boolean>; // ancient
        host-statistics-max <integer>; // ancient
        hostname ( <quoted_string> | none );
        inline-signing <boolean>;
        interface-interval <duration>;
        ixfr-from-differences ( primary | master | secondary | slave |
            <boolean> );
        keep-response-order { <address_match_element>; ... };
        key-directory <quoted_string>;
        lame-ttl <duration>;
        listen-on [ port <integer> ] [ dscp
            <integer> ] {
            <address_match_element>; ... }; // may occur multiple times
        listen-on-v6 [ port <integer> ] [ dscp
            <integer> ] {
            <address_match_element>; ... }; // may occur multiple times
        lmdb-mapsize <sizeval>; // non-operational
        lock-file ( <quoted_string> | none );
        maintain-ixfr-base <boolean>; // ancient
        managed-keys-directory <quoted_string>;
        masterfile-format ( map | raw | text );
        masterfile-style ( full | relative );
        match-mapped-addresses <boolean>;
        max-acache-size ( unlimited | <sizeval> ); // obsolete
        max-cache-size ( default | unlimited | <sizeval> | <percentage> );
        max-cache-ttl <duration>;
        max-clients-per-query <integer>;
        max-ixfr-log-size ( default | unlimited | <sizeval> ); // ancient
        max-journal-size ( default | unlimited | <sizeval> );
        max-ncache-ttl <duration>;
        max-records <integer>;
        max-recursion-depth <integer>;
        max-recursion-queries <integer>;
        max-refresh-time <integer>;
        max-retry-time <integer>;
        max-rsa-exponent-size <integer>;
        max-stale-ttl <duration>;
        max-transfer-idle-in <integer>;
        max-transfer-idle-out <integer>;
        max-transfer-time-in <integer>;
        max-transfer-time-out <integer>;
        max-udp-size <integer>;
        max-zone-ttl ( unlimited | <duration> );
        memstatistics <boolean>;
        memstatistics-file <quoted_string>;
        message-compression <boolean>;
        min-cache-ttl <duration>;
        min-ncache-ttl <duration>;
        min-refresh-time <integer>;
        min-retry-time <integer>;
        min-roots <integer>; // ancient
        minimal-any <boolean>;
        minimal-responses ( no-auth | no-auth-recursive | <boolean> );
        multi-master <boolean>;
        multiple-cnames <boolean>; // ancient
        named-xfer <quoted_string>; // ancient
        new-zones-directory <quoted_string>;
        no-case-compress { <address_match_element>; ... };
        nocookie-udp-size <integer>;
        nosit-udp-size <integer>; // obsolete
        notify ( explicit | master-only | <boolean> );
        notify-delay <integer>;
        notify-rate <integer>;
        notify-source ( <ipv4_address> | * ) [ port ( <integer> | * ) ] [
            dscp <integer> ];
        notify-source-v6 ( <ipv6_address> | * ) [ port ( <integer> | * ) ]
            [ dscp <integer> ];
        notify-to-soa <boolean>;
        nsec3-test-zone <boolean>; // test only
        nta-lifetime <duration>;
        nta-recheck <duration>;
        nxdomain-redirect <string>;
        pid-file ( <quoted_string> | none );
        port <integer>;
        preferred-glue <string>;
        prefetch <integer> [ <integer> ];
        provide-ixfr <boolean>;
        qname-minimization ( strict | relaxed | disabled | off );
        query-source ( ( [ address ] ( <ipv4_address> | * ) [ port (
            <integer> | * ) ] ) | ( [ [ address ] ( <ipv4_address> | * ) ]
            port ( <integer> | * ) ) ) [ dscp <integer> ];
        query-source-v6 ( ( [ address ] ( <ipv6_address> | * ) [ port (
            <integer> | * ) ] ) | ( [ [ address ] ( <ipv6_address> | * ) ]
            port ( <integer> | * ) ) ) [ dscp <integer> ];
        querylog <boolean>;
        queryport-pool-ports <integer>; // obsolete
        queryport-pool-updateinterval <integer>; // obsolete
        random-device ( <quoted_string> | none );
        rate-limit {
                all-per-second <integer>;
                errors-per-second <integer>;
                exempt-clients { <address_match_element>; ... };
                ipv4-prefix-length <integer>;
                ipv6-prefix-length <integer>;
                log-only <boolean>;
                max-table-size <integer>;
                min-table-size <integer>;
                nodata-per-second <integer>;
                nxdomains-per-second <integer>;
                qps-scale <integer>;
                referrals-per-second <integer>;
                responses-per-second <integer>;
                slip <integer>;
                window <integer>;
        };
        recursing-file <quoted_string>;
        recursion <boolean>;
        recursive-clients <integer>;
        request-expire <boolean>;
        request-ixfr <boolean>;
        request-nsid <boolean>;
        request-sit <boolean>; // obsolete
        require-server-cookie <boolean>;
        reserved-sockets <integer>;
        resolver-nonbackoff-tries <integer>;
        resolver-query-timeout <integer>;
        resolver-retry-interval <integer>;
        response-padding { <address_match_element>; ... } block-size
            <integer>;
        response-policy { zone <string> [ add-soa <boolean> ] [ log
            <boolean> ] [ max-policy-ttl <duration> ] [ min-update-interval
            <duration> ] [ policy ( cname | disabled | drop | given | no-op
            | nodata | nxdomain | passthru | tcp-only <quoted_string> ) ] [
            recursive-only <boolean> ] [ nsip-enable <boolean> ] [
            nsdname-enable <boolean> ]; ... } [ add-soa <boolean> ] [
            break-dnssec <boolean> ] [ max-policy-ttl <duration> ] [
            min-update-interval <duration> ] [ min-ns-dots <integer> ] [
            nsip-wait-recurse <boolean> ] [ qname-wait-recurse <boolean> ]
            [ recursive-only <boolean> ] [ nsip-enable <boolean> ] [
            nsdname-enable <boolean> ] [ dnsrps-enable <boolean> ] [
            dnsrps-options { <unspecified-text> } ];
        rfc2308-type1 <boolean>; // ancient
        root-delegation-only [ exclude { <string>; ... } ];
        root-key-sentinel <boolean>;
        rrset-order { [ class <string> ] [ type <string> ] [ name
            <quoted_string> ] <string> <string>; ... };
        secroots-file <quoted_string>;
        send-cookie <boolean>;
        serial-queries <integer>; // ancient
        serial-query-rate <integer>;
        serial-update-method ( date | increment | unixtime );
        server-id ( <quoted_string> | none | hostname );
        servfail-ttl <duration>;
        session-keyalg <string>;
        session-keyfile ( <quoted_string> | none );
        session-keyname <string>;
        sig-signing-nodes <integer>;
        sig-signing-signatures <integer>;
        sig-signing-type <integer>;
        sig-validity-interval <integer> [ <integer> ];
        sit-secret <string>; // obsolete
        sortlist { <address_match_element>; ... };
        stacksize ( default | unlimited | <sizeval> );
        stale-answer-enable <boolean>;
        stale-answer-ttl <duration>;
        startup-notify-rate <integer>;
        statistics-file <quoted_string>;
        statistics-interval <integer>; // ancient
        suppress-initial-notify <boolean>; // not yet implemented
        synth-from-dnssec <boolean>;
        tcp-advertised-timeout <integer>;
        tcp-clients <integer>;
        tcp-idle-timeout <integer>;
        tcp-initial-timeout <integer>;
        tcp-keepalive-timeout <integer>;
        tcp-listen-queue <integer>;
        tkey-dhkey <quoted_string> <integer>;
        tkey-domain <quoted_string>;
        tkey-gssapi-credential <quoted_string>;
        tkey-gssapi-keytab <quoted_string>;
        topology { <address_match_element>; ... }; // ancient
        transfer-format ( many-answers | one-answer );
        transfer-message-size <integer>;
        transfer-source ( <ipv4_address> | * ) [ port ( <integer> | * ) ] [
            dscp <integer> ];
        transfer-source-v6 ( <ipv6_address> | * ) [ port ( <integer> | * )
            ] [ dscp <integer> ];
        transfers-in <integer>;
        transfers-out <integer>;
        transfers-per-ns <integer>;
        treat-cr-as-space <boolean>; // ancient
        trust-anchor-telemetry <boolean>; // experimental
        try-tcp-refresh <boolean>;
        update-check-ksk <boolean>;
        use-alt-transfer-source <boolean>;
        use-id-pool <boolean>; // ancient
        use-ixfr <boolean>; // obsolete
        use-queryport-pool <boolean>; // obsolete
        use-v4-udp-ports { <portrange>; ... };
        use-v6-udp-ports { <portrange>; ... };
        v6-bias <integer>;
        validate-except { <string>; ... };
        version ( <quoted_string> | none );
        zero-no-soa-ttl <boolean>;
        zero-no-soa-ttl-cache <boolean>;
        zone-statistics ( full | terse | none | <boolean> );
};

plugin ( query ) <string> [ { <unspecified-text>
    } ]; // may occur multiple times

server <netprefix> {
        bogus <boolean>;
        edns <boolean>;
        edns-udp-size <integer>;
        edns-version <integer>;
        keys <server_key>;
        max-udp-size <integer>;
        notify-source ( <ipv4_address> | * ) [ port ( <integer> | * ) ] [
            dscp <integer> ];
        notify-source-v6 ( <ipv6_address> | * ) [ port ( <integer> | * ) ]
            [ dscp <integer> ];
        padding <integer>;
        provide-ixfr <boolean>;
        query-source ( ( [ address ] ( <ipv4_address> | * ) [ port (
            <integer> | * ) ] ) | ( [ [ address ] ( <ipv4_address> | * ) ]
            port ( <integer> | * ) ) ) [ dscp <integer> ];
        query-source-v6 ( ( [ address ] ( <ipv6_address> | * ) [ port (
            <integer> | * ) ] ) | ( [ [ address ] ( <ipv6_address> | * ) ]
            port ( <integer> | * ) ) ) [ dscp <integer> ];
        request-expire <boolean>;
        request-ixfr <boolean>;
        request-nsid <boolean>;
        request-sit <boolean>; // obsolete
        send-cookie <boolean>;
        support-ixfr <boolean>; // obsolete
        tcp-keepalive <boolean>;
        tcp-only <boolean>;
        transfer-format ( many-answers | one-answer );
        transfer-source ( <ipv4_address> | * ) [ port ( <integer> | * ) ] [
            dscp <integer> ];
        transfer-source-v6 ( <ipv6_address> | * ) [ port ( <integer> | * )
            ] [ dscp <integer> ];
        transfers <integer>;
}; // may occur multiple times

statistics-channels {
        inet ( <ipv4_address> | <ipv6_address> |
            * ) [ port ( <integer> | * ) ] [
            allow { <address_match_element>; ...
            } ]; // may occur multiple times
}; // may occur multiple times

trust-anchors { <string> ( static-key |
    initial-key | static-ds | initial-ds )
    <integer> <integer> <integer>
    <quoted_string>; ... }; // may occur multiple times

trusted-keys { <string> <integer>
    <integer> <integer>
    <quoted_string>; ... }; // may occur multiple times, deprecated

view <string> [ <class> ] {
        acache-cleaning-interval <integer>; // obsolete
        acache-enable <boolean>; // obsolete
        additional-from-auth <boolean>; // obsolete
        additional-from-cache <boolean>; // obsolete
        allow-new-zones <boolean>;
        allow-notify { <address_match_element>; ... };
        allow-query { <address_match_element>; ... };
        allow-query-cache { <address_match_element>; ... };
        allow-query-cache-on { <address_match_element>; ... };
        allow-query-on { <address_match_element>; ... };
        allow-recursion { <address_match_element>; ... };
        allow-recursion-on { <address_match_element>; ... };
        allow-transfer { <address_match_element>; ... };
        allow-update { <address_match_element>; ... };
        allow-update-forwarding { <address_match_element>; ... };
        allow-v6-synthesis { <address_match_element>; ... }; // obsolete
        also-notify [ port <integer> ] [ dscp <integer> ] { ( <masters> |
            <ipv4_address> [ port <integer> ] | <ipv6_address> [ port
            <integer> ] ) [ key <string> ]; ... };
        alt-transfer-source ( <ipv4_address> | * ) [ port ( <integer> | * )
            ] [ dscp <integer> ];
        alt-transfer-source-v6 ( <ipv6_address> | * ) [ port ( <integer> |
            * ) ] [ dscp <integer> ];
        attach-cache <string>;
        auth-nxdomain <boolean>; // default changed
        auto-dnssec ( allow | maintain | off );
        cache-file <quoted_string>;
        catalog-zones { zone <string> [ default-masters [ port <integer> ]
            [ dscp <integer> ] { ( <masters> | <ipv4_address> [ port
            <integer> ] | <ipv6_address> [ port <integer> ] ) [ key
            <string> ]; ... } ] [ zone-directory <quoted_string> ] [
            in-memory <boolean> ] [ min-update-interval <duration> ]; ... };
        check-dup-records ( fail | warn | ignore );
        check-integrity <boolean>;
        check-mx ( fail | warn | ignore );
        check-mx-cname ( fail | warn | ignore );
        check-names ( primary | master |
            secondary | slave | response ) (
            fail | warn | ignore ); // may occur multiple times
        check-sibling <boolean>;
        check-spf ( warn | ignore );
        check-srv-cname ( fail | warn | ignore );
        check-wildcard <boolean>;
        cleaning-interval <integer>; // obsolete
        clients-per-query <integer>;
        deny-answer-addresses { <address_match_element>; ... } [
            except-from { <string>; ... } ];
        deny-answer-aliases { <string>; ... } [ except-from { <string>; ...
            } ];
        dialup ( notify | notify-passive | passive | refresh | <boolean> );
        disable-algorithms <string> { <string>;
            ... }; // may occur multiple times
        disable-ds-digests <string> { <string>;
            ... }; // may occur multiple times
        disable-empty-zone <string>; // may occur multiple times
        dlz <string> {
                database <string>;
                search <boolean>;
        }; // may occur multiple times
        dns64 <netprefix> {
                break-dnssec <boolean>;
                clients { <address_match_element>; ... };
                exclude { <address_match_element>; ... };
                mapped { <address_match_element>; ... };
                recursive-only <boolean>;
                suffix <ipv6_address>;
        }; // may occur multiple times
        dns64-contact <string>;
        dns64-server <string>;
        dnskey-sig-validity <integer>;
        dnsrps-enable <boolean>; // not configured
        dnsrps-options { <unspecified-text> }; // not configured
        dnssec-accept-expired <boolean>;
        dnssec-dnskey-kskonly <boolean>;
        dnssec-enable <boolean>; // obsolete
        dnssec-loadkeys-interval <integer>;
        dnssec-lookaside ( <string>
            trust-anchor <string> |
            auto | no ); // obsolete, may occur multiple times
        dnssec-must-be-secure <string> <boolean>; // may occur multiple times
        dnssec-policy <string>;
        dnssec-secure-to-insecure <boolean>;
        dnssec-update-mode ( maintain | no-resign );
        dnssec-validation ( yes | no | auto );
        dnstap { ( all | auth | client | forwarder |
            resolver | update ) [ ( query | response ) ];
            ... }; // not configured
        dual-stack-servers [ port <integer> ] { ( <quoted_string> [ port
            <integer> ] [ dscp <integer> ] | <ipv4_address> [ port
            <integer> ] [ dscp <integer> ] | <ipv6_address> [ port
            <integer> ] [ dscp <integer> ] ); ... };
        dyndb <string> <quoted_string> {
            <unspecified-text> }; // may occur multiple times
        edns-udp-size <integer>;
        empty-contact <string>;
        empty-server <string>;
        empty-zones-enable <boolean>;
        fetch-glue <boolean>; // ancient
        fetch-quota-params <integer> <fixedpoint> <fixedpoint> <fixedpoint>;
        fetches-per-server <integer> [ ( drop | fail ) ];
        fetches-per-zone <integer> [ ( drop | fail ) ];
        filter-aaaa { <address_match_element>; ... }; // obsolete
        filter-aaaa-on-v4 <boolean>; // obsolete
        filter-aaaa-on-v6 <boolean>; // obsolete
        forward ( first | only );
        forwarders [ port <integer> ] [ dscp <integer> ] { ( <ipv4_address>
            | <ipv6_address> ) [ port <integer> ] [ dscp <integer> ]; ... };
        glue-cache <boolean>;
        inline-signing <boolean>;
        ixfr-from-differences ( primary | master | secondary | slave |
            <boolean> );
        key <string> {
                algorithm <string>;
                secret <string>;
        }; // may occur multiple times
        key-directory <quoted_string>;
        lame-ttl <duration>;
        lmdb-mapsize <sizeval>; // non-operational
        maintain-ixfr-base <boolean>; // ancient
        managed-keys { <string> (
            static-key | initial-key
            | static-ds | initial-ds
            ) <integer> <integer>
            <integer>
            <quoted_string>; ... }; // may occur multiple times, deprecated
        masterfile-format ( map | raw | text );
        masterfile-style ( full | relative );
        match-clients { <address_match_element>; ... };
        match-destinations { <address_match_element>; ... };
        match-recursive-only <boolean>;
        max-acache-size ( unlimited | <sizeval> ); // obsolete
        max-cache-size ( default | unlimited | <sizeval> | <percentage> );
        max-cache-ttl <duration>;
        max-clients-per-query <integer>;
        max-ixfr-log-size ( default | unlimited | <sizeval> ); // ancient
        max-journal-size ( default | unlimited | <sizeval> );
        max-ncache-ttl <duration>;
        max-records <integer>;
        max-recursion-depth <integer>;
        max-recursion-queries <integer>;
        max-refresh-time <integer>;
        max-retry-time <integer>;
        max-stale-ttl <duration>;
        max-transfer-idle-in <integer>;
        max-transfer-idle-out <integer>;
        max-transfer-time-in <integer>;
        max-transfer-time-out <integer>;
        max-udp-size <integer>;
        max-zone-ttl ( unlimited | <duration> );
        message-compression <boolean>;
        min-cache-ttl <duration>;
        min-ncache-ttl <duration>;
        min-refresh-time <integer>;
        min-retry-time <integer>;
        min-roots <integer>; // ancient
        minimal-any <boolean>;
        minimal-responses ( no-auth | no-auth-recursive | <boolean> );
        multi-master <boolean>;
        new-zones-directory <quoted_string>;
        no-case-compress { <address_match_element>; ... };
        nocookie-udp-size <integer>;
        nosit-udp-size <integer>; // obsolete
        notify ( explicit | master-only | <boolean> );
        notify-delay <integer>;
        notify-source ( <ipv4_address> | * ) [ port ( <integer> | * ) ] [
            dscp <integer> ];
        notify-source-v6 ( <ipv6_address> | * ) [ port ( <integer> | * ) ]
            [ dscp <integer> ];
        notify-to-soa <boolean>;
        nsec3-test-zone <boolean>; // test only
        nta-lifetime <duration>;
        nta-recheck <duration>;
        nxdomain-redirect <string>;
        plugin ( query ) <string> [ {
            <unspecified-text> } ]; // may occur multiple times
        preferred-glue <string>;
        prefetch <integer> [ <integer> ];
        provide-ixfr <boolean>;
        qname-minimization ( strict | relaxed | disabled | off );
        query-source ( ( [ address ] ( <ipv4_address> | * ) [ port (
            <integer> | * ) ] ) | ( [ [ address ] ( <ipv4_address> | * ) ]
            port ( <integer> | * ) ) ) [ dscp <integer> ];
        query-source-v6 ( ( [ address ] ( <ipv6_address> | * ) [ port (
            <integer> | * ) ] ) | ( [ [ address ] ( <ipv6_address> | * ) ]
            port ( <integer> | * ) ) ) [ dscp <integer> ];
        queryport-pool-ports <integer>; // obsolete
        queryport-pool-updateinterval <integer>; // obsolete
        rate-limit {
                all-per-second <integer>;
                errors-per-second <integer>;
                exempt-clients { <address_match_element>; ... };
                ipv4-prefix-length <integer>;
                ipv6-prefix-length <integer>;
                log-only <boolean>;
                max-table-size <integer>;
                min-table-size <integer>;
                nodata-per-second <integer>;
                nxdomains-per-second <integer>;
                qps-scale <integer>;
                referrals-per-second <integer>;
                responses-per-second <integer>;
                slip <integer>;
                window <integer>;
        };
        recursion <boolean>;
        request-expire <boolean>;
        request-ixfr <boolean>;
        request-nsid <boolean>;
        request-sit <boolean>; // obsolete
        require-server-cookie <boolean>;
        resolver-nonbackoff-tries <integer>;
        resolver-query-timeout <integer>;
        resolver-retry-interval <integer>;
        response-padding { <address_match_element>; ... } block-size
            <integer>;
        response-policy { zone <string> [ add-soa <boolean> ] [ log
            <boolean> ] [ max-policy-ttl <duration> ] [ min-update-interval
            <duration> ] [ policy ( cname | disabled | drop | given | no-op
            | nodata | nxdomain | passthru | tcp-only <quoted_string> ) ] [
            recursive-only <boolean> ] [ nsip-enable <boolean> ] [
            nsdname-enable <boolean> ]; ... } [ add-soa <boolean> ] [
            break-dnssec <boolean> ] [ max-policy-ttl <duration> ] [
            min-update-interval <duration> ] [ min-ns-dots <integer> ] [
            nsip-wait-recurse <boolean> ] [ qname-wait-recurse <boolean> ]
            [ recursive-only <boolean> ] [ nsip-enable <boolean> ] [
            nsdname-enable <boolean> ] [ dnsrps-enable <boolean> ] [
            dnsrps-options { <unspecified-text> } ];
        rfc2308-type1 <boolean>; // ancient
        root-delegation-only [ exclude { <string>; ... } ];
        root-key-sentinel <boolean>;
        rrset-order { [ class <string> ] [ type <string> ] [ name
            <quoted_string> ] <string> <string>; ... };
        send-cookie <boolean>;
        serial-update-method ( date | increment | unixtime );
        server <netprefix> {
                bogus <boolean>;
                edns <boolean>;
                edns-udp-size <integer>;
                edns-version <integer>;
                keys <server_key>;
                max-udp-size <integer>;
                notify-source ( <ipv4_address> | * ) [ port ( <integer> | *
                    ) ] [ dscp <integer> ];
                notify-source-v6 ( <ipv6_address> | * ) [ port ( <integer>
                    | * ) ] [ dscp <integer> ];
                padding <integer>;
                provide-ixfr <boolean>;
                query-source ( ( [ address ] ( <ipv4_address> | * ) [ port
                    ( <integer> | * ) ] ) | ( [ [ address ] (
                    <ipv4_address> | * ) ] port ( <integer> | * ) ) ) [
                    dscp <integer> ];
                query-source-v6 ( ( [ address ] ( <ipv6_address> | * ) [
                    port ( <integer> | * ) ] ) | ( [ [ address ] (
                    <ipv6_address> | * ) ] port ( <integer> | * ) ) ) [
                    dscp <integer> ];
                request-expire <boolean>;
                request-ixfr <boolean>;
                request-nsid <boolean>;
                request-sit <boolean>; // obsolete
                send-cookie <boolean>;
                support-ixfr <boolean>; // obsolete
                tcp-keepalive <boolean>;
                tcp-only <boolean>;
                transfer-format ( many-answers | one-answer );
                transfer-source ( <ipv4_address> | * ) [ port ( <integer> |
                    * ) ] [ dscp <integer> ];
                transfer-source-v6 ( <ipv6_address> | * ) [ port (
                    <integer> | * ) ] [ dscp <integer> ];
                transfers <integer>;
        }; // may occur multiple times
        servfail-ttl <duration>;
        sig-signing-nodes <integer>;
        sig-signing-signatures <integer>;
        sig-signing-type <integer>;
        sig-validity-interval <integer> [ <integer> ];
        sortlist { <address_match_element>; ... };
        stale-answer-enable <boolean>;
        stale-answer-ttl <duration>;
        suppress-initial-notify <boolean>; // not yet implemented
        synth-from-dnssec <boolean>;
        topology { <address_match_element>; ... }; // ancient
        transfer-format ( many-answers | one-answer );
        transfer-source ( <ipv4_address> | * ) [ port ( <integer> | * ) ] [
            dscp <integer> ];
        transfer-source-v6 ( <ipv6_address> | * ) [ port ( <integer> | * )
            ] [ dscp <integer> ];
        trust-anchor-telemetry <boolean>; // experimental
        trust-anchors { <string> ( static-key |
            initial-key | static-ds | initial-ds
            ) <integer> <integer> <integer>
            <quoted_string>; ... }; // may occur multiple times
        trusted-keys { <string>
            <integer> <integer>
            <integer>
            <quoted_string>; ... }; // may occur multiple times, deprecated
        try-tcp-refresh <boolean>;
        update-check-ksk <boolean>;
        use-alt-transfer-source <boolean>;
        use-queryport-pool <boolean>; // obsolete
        v6-bias <integer>;
        validate-except { <string>; ... };
        zero-no-soa-ttl <boolean>;
        zero-no-soa-ttl-cache <boolean>;
        zone <string> [ <class> ] {
                allow-notify { <address_match_element>; ... };
                allow-query { <address_match_element>; ... };
                allow-query-on { <address_match_element>; ... };
                allow-transfer { <address_match_element>; ... };
                allow-update { <address_match_element>; ... };
                allow-update-forwarding { <address_match_element>; ... };
                also-notify [ port <integer> ] [ dscp <integer> ] { (
                    <masters> | <ipv4_address> [ port <integer> ] |
                    <ipv6_address> [ port <integer> ] ) [ key <string> ];
                    ... };
                alt-transfer-source ( <ipv4_address> | * ) [ port (
                    <integer> | * ) ] [ dscp <integer> ];
                alt-transfer-source-v6 ( <ipv6_address> | * ) [ port (
                    <integer> | * ) ] [ dscp <integer> ];
                auto-dnssec ( allow | maintain | off );
                check-dup-records ( fail | warn | ignore );
                check-integrity <boolean>;
                check-mx ( fail | warn | ignore );
                check-mx-cname ( fail | warn | ignore );
                check-names ( fail | warn | ignore );
                check-sibling <boolean>;
                check-spf ( warn | ignore );
                check-srv-cname ( fail | warn | ignore );
                check-wildcard <boolean>;
                database <string>;
                delegation-only <boolean>;
                dialup ( notify | notify-passive | passive | refresh |
                    <boolean> );
                dlz <string>;
                dnskey-sig-validity <integer>;
                dnssec-dnskey-kskonly <boolean>;
                dnssec-loadkeys-interval <integer>;
                dnssec-policy <string>;
                dnssec-secure-to-insecure <boolean>;
                dnssec-update-mode ( maintain | no-resign );
                file <quoted_string>;
                forward ( first | only );
                forwarders [ port <integer> ] [ dscp <integer> ] { (
                    <ipv4_address> | <ipv6_address> ) [ port <integer> ] [
                    dscp <integer> ]; ... };
                in-view <string>;
                inline-signing <boolean>;
                ixfr-base <quoted_string>; // ancient
                ixfr-from-differences <boolean>;
                ixfr-tmp-file <quoted_string>; // ancient
                journal <quoted_string>;
                key-directory <quoted_string>;
                maintain-ixfr-base <boolean>; // ancient
                masterfile-format ( map | raw | text );
                masterfile-style ( full | relative );
                masters [ port <integer> ] [ dscp <integer> ] { ( <masters>
                    | <ipv4_address> [ port <integer> ] | <ipv6_address> [
                    port <integer> ] ) [ key <string> ]; ... };
                max-ixfr-log-size ( default | unlimited |
                    <sizeval> ); // ancient
                max-journal-size ( default | unlimited | <sizeval> );
                max-records <integer>;
                max-refresh-time <integer>;
                max-retry-time <integer>;
                max-transfer-idle-in <integer>;
                max-transfer-idle-out <integer>;
                max-transfer-time-in <integer>;
                max-transfer-time-out <integer>;
                max-zone-ttl ( unlimited | <duration> );
                min-refresh-time <integer>;
                min-retry-time <integer>;
                multi-master <boolean>;
                notify ( explicit | master-only | <boolean> );
                notify-delay <integer>;
                notify-source ( <ipv4_address> | * ) [ port ( <integer> | *
                    ) ] [ dscp <integer> ];
                notify-source-v6 ( <ipv6_address> | * ) [ port ( <integer>
                    | * ) ] [ dscp <integer> ];
                notify-to-soa <boolean>;
                nsec3-test-zone <boolean>; // test only
                pubkey <integer> <integer> <integer>
                    <quoted_string>; // ancient
                request-expire <boolean>;
                request-ixfr <boolean>;
                serial-update-method ( date | increment | unixtime );
                server-addresses { ( <ipv4_address> | <ipv6_address> ); ... };
                server-names { <string>; ... };
                sig-signing-nodes <integer>;
                sig-signing-signatures <integer>;
                sig-signing-type <integer>;
                sig-validity-interval <integer> [ <integer> ];
                transfer-source ( <ipv4_address> | * ) [ port ( <integer> |
                    * ) ] [ dscp <integer> ];
                transfer-source-v6 ( <ipv6_address> | * ) [ port (
                    <integer> | * ) ] [ dscp <integer> ];
                try-tcp-refresh <boolean>;
                type ( primary | master | secondary | slave | mirror |
                    delegation-only | forward | hint | redirect |
                    static-stub | stub );
                update-check-ksk <boolean>;
                update-policy ( local | { ( deny | grant ) <string> (
                    6to4-self | external | krb5-self | krb5-selfsub |
                    krb5-subdomain | ms-self | ms-selfsub | ms-subdomain |
                    name | self | selfsub | selfwild | subdomain | tcp-self
                    | wildcard | zonesub ) [ <string> ] <rrtypelist>; ... };
                use-alt-transfer-source <boolean>;
                zero-no-soa-ttl <boolean>;
                zone-statistics ( full | terse | none | <boolean> );
        }; // may occur multiple times
        zone-statistics ( full | terse | none | <boolean> );
}; // may occur multiple times

zone <string> [ <class> ] {
        allow-notify { <address_match_element>; ... };
        allow-query { <address_match_element>; ... };
        allow-query-on { <address_match_element>; ... };
        allow-transfer { <address_match_element>; ... };
        allow-update { <address_match_element>; ... };
        allow-update-forwarding { <address_match_element>; ... };
        also-notify [ port <integer> ] [ dscp <integer> ] { ( <masters> |
            <ipv4_address> [ port <integer> ] | <ipv6_address> [ port
            <integer> ] ) [ key <string> ]; ... };
        alt-transfer-source ( <ipv4_address> | * ) [ port ( <integer> | * )
            ] [ dscp <integer> ];
        alt-transfer-source-v6 ( <ipv6_address> | * ) [ port ( <integer> |
            * ) ] [ dscp <integer> ];
        auto-dnssec ( allow | maintain | off );
        check-dup-records ( fail | warn | ignore );
        check-integrity <boolean>;
        check-mx ( fail | warn | ignore );
        check-mx-cname ( fail | warn | ignore );
        check-names ( fail | warn | ignore );
        check-sibling <boolean>;
        check-spf ( warn | ignore );
        check-srv-cname ( fail | warn | ignore );
        check-wildcard <boolean>;
        database <string>;
        delegation-only <boolean>;
        dialup ( notify | notify-passive | passive | refresh | <boolean> );
        dlz <string>;
        dnskey-sig-validity <integer>;
        dnssec-dnskey-kskonly <boolean>;
        dnssec-loadkeys-interval <integer>;
        dnssec-policy <string>;
        dnssec-secure-to-insecure <boolean>;
        dnssec-update-mode ( maintain | no-resign );
        file <quoted_string>;
        forward ( first | only );
        forwarders [ port <integer> ] [ dscp <integer> ] { ( <ipv4_address>
            | <ipv6_address> ) [ port <integer> ] [ dscp <integer> ]; ... };
        in-view <string>;
        inline-signing <boolean>;
        ixfr-base <quoted_string>; // ancient
        ixfr-from-differences <boolean>;
        ixfr-tmp-file <quoted_string>; // ancient
        journal <quoted_string>;
        key-directory <quoted_string>;
        maintain-ixfr-base <boolean>; // ancient
        masterfile-format ( map | raw | text );
        masterfile-style ( full | relative );
        masters [ port <integer> ] [ dscp <integer> ] { ( <masters> |
            <ipv4_address> [ port <integer> ] | <ipv6_address> [ port
            <integer> ] ) [ key <string> ]; ... };
        max-ixfr-log-size ( default | unlimited | <sizeval> ); // ancient
        max-journal-size ( default | unlimited | <sizeval> );
        max-records <integer>;
        max-refresh-time <integer>;
        max-retry-time <integer>;
        max-transfer-idle-in <integer>;
        max-transfer-idle-out <integer>;
        max-transfer-time-in <integer>;
        max-transfer-time-out <integer>;
        max-zone-ttl ( unlimited | <duration> );
        min-refresh-time <integer>;
        min-retry-time <integer>;
        multi-master <boolean>;
        notify ( explicit | master-only | <boolean> );
        notify-delay <integer>;
        notify-source ( <ipv4_address> | * ) [ port ( <integer> | * ) ] [
            dscp <integer> ];
        notify-source-v6 ( <ipv6_address> | * ) [ port ( <integer> | * ) ]
            [ dscp <integer> ];
        notify-to-soa <boolean>;
        nsec3-test-zone <boolean>; // test only
        pubkey <integer> <integer> <integer> <quoted_string>; // ancient
        request-expire <boolean>;
        request-ixfr <boolean>;
        serial-update-method ( date | increment | unixtime );
        server-addresses { ( <ipv4_address> | <ipv6_address> ); ... };
        server-names { <string>; ... };
        sig-signing-nodes <integer>;
        sig-signing-signatures <integer>;
        sig-signing-type <integer>;
        sig-validity-interval <integer> [ <integer> ];
        transfer-source ( <ipv4_address> | * ) [ port ( <integer> | * ) ] [
            dscp <integer> ];
        transfer-source-v6 ( <ipv6_address> | * ) [ port ( <integer> | * )
            ] [ dscp <integer> ];
        try-tcp-refresh <boolean>;
        type ( primary | master | secondary | slave | mirror |
            delegation-only | forward | hint | redirect | static-stub |
            stub );
        update-check-ksk <boolean>;
        update-policy ( local | { ( deny | grant ) <string> ( 6to4-self |
            external | krb5-self | krb5-selfsub | krb5-subdomain | ms-self
            | ms-selfsub | ms-subdomain | name | self | selfsub | selfwild
            | subdomain | tcp-self | wildcard | zonesub ) [ <string> ]
            <rrtypelist>; ... };
        use-alt-transfer-source <boolean>;
        zero-no-soa-ttl <boolean>;
        zone-statistics ( full | terse | none | <boolean> );
}; // may occur multiple times

