Provided by: maradns_1.4.02-1_i386 bug

NAME

       mararc - Format of the mararc zone file that MaraDNS uses

MARARC FILE FORMAT

       Mararc files use a syntax that is a subset of Python 2.2.3 syntax. In
       particular, Python 2.2.3 (and possibly other versions of Python) can
       read a properly formatted mararc file without error.

       Unlike Python, however, a mararc file can only use certain variable
       names, and the variables can only be declared as described below.

COMMENTS

       Comments (lines ignored by the MaraDNS parser) start with the '#'
       character, like this:

       # This is a comment

       The MaraDNS parser also ignores lines which contain only white space.

OPERATORS

       The MaraRC file supports two operators: = and +=

       The = operator can be used to assign both numeric and string values

       The += operator can only be used on string values, and concatenates the
       value to the right of the += operator to the string specified to the
       left of the += operator.

       Examples:

       ipv4_bind_addresses = "10.2.19.83"
       ipv4_bind_addresses += ",10.2.66.74"
       ipv4_bind_addresses += ",10.3.87.13"

       ipv4_bind_addresses now has the value
       "10.2.19.83,10.2.66.74,10.3.87.13"

       ipv4_alias["icann"] = "198.41.0.4"
       ipv4_alias["icann"] += ",192.228.79.201"
       ipv4_alias["icann"] += ",192.33.4.12,128.8.10.90"

MARARC VARIABLES

       Follows is a listing of variables that can be declared in the mararc
       file.

DICTIONARY VARIABLE FORMAT

       A dictionary variable is an array that can have multiple elements.
       Unlike a traditional array, these arrays are indexed by strings instead
       of numbers. These are analogous to associative arrays, or what Perl
       somewhat inaccurately calls hashes.

       The syntax of a dictionary variable is in the following form:

       name["index"] = "value"

       Where name is the name of the dictionary variable, index is the index
       of the array, and value is the value stored at that index.

       Every time we have a dictionary-type variable (such as csv2), we must
       first initialize it using a line in the following form:

       csv2 = {}

       Here, csv2 is the name of the "dictionary" variable that we are
       initializing.

DICTIONARY VARIABLES

       Here is a listing of all "dictionary"-style variables that MaraDNS
       uses:

    csv2

       The csv2 dictionary variable stores all of the zone names and file
       names for the zone files that MaraDNS uses. Note that csv2 files are
       read after MaraDNS is chrooted. Hence the filename is relative to the
       chroot_dir.  Example:

       csv2["example.net."] = "db.example.net"

       See csv2(5) for a description of this file's format.

       The dictionary index (zone name) can not have a * in it. If it does,
       MaraDNS will terminate with an "Illegal zone name" error.

    csv1

       csv1: Used to indicate the filename to use for a given zone stored in
       the legacy csv1 zone file format. This is primarily for compatibility
       with people who have maradns-1.0 zone files.

       csv1["zone"] = "filename"

       csv1: A pipe-separated-file. See csv1(5).

       zone: the zone that file in question is authoritative for

       filename: the file with the CSV1 zone data

       Note that csv1 files are read after MaraDNS is chrooted, and, hence the
       filename is relative to the chroot_dir.

       See the csv1(5) man page for more information on this file format.

    ipv4_alias

       ipv4_alias: Used to give nicknames or aliases for ip/netmask pairs for
       ipv4 (standard 32-bit) IP addresses.

       ipv4_alias["name"] = "ip1/netmask,ip2/netmask,etc"

       name: The name of the alias in question

       ip: The ip portion of an ip/netmask pair

       netmask: the mask portion of an ip/netmask pair

       ,: Used to separate ip/netmask pairs. Spaces may be placed before or
       after this comma.

       An ip is in dotted-decimal format, e.g. "10.1.2.3".

       The netmask can be in one of two formats: A single number between 1 and
       32, which indicates the number of leading "1" bits in the netmask, or a
       4-digit dotted-decimal netmask.

       The netmask is used to specify a range of IPs.

    ipv4_alias examples

       10.1.1.1/24 indicates that any ip from 10.1.1.0 to 10.1.1.255 will
       match.

       10.1.1.1/255.255.255.0 is identical to 10.1.1.1/24

       10.2.3.4/16 indicates that any ip from 10.2.0.0 to 10.2.255.255 will
       match.

       10.2.3.4/255.255.0.0 is identical to 10.2.3.4/16

       127.0.0.0/8 indicates that any ip with "127" as the first octet
       (number) will match.

       127.0.0.0/255.0.0.0 is identical to 127.0.0.0/8

       The netmask is optional, and, if not present, indicates that only a
       single IP will "match". e.g:

       10.9.9.9/32, 10.9.9.9/255.255.255.255, and 10.9.9.9 are all
       functionally identical, and indicate that only the ip 10.9.9.9 will
       match.

       The significance of "match" depends on what we use the ipv4 alias for.

       ipv4 aliases can nest. E.g:

       ipv4_alias["susan"] = "10.6.7.8/24"
       ipv4_alias["office"] = "susan,10.9.9.9"

       Where "susan" in the "office" alias matches the value of the ipv4_alias
       susan.

       Multiple levels of nesting are allowed. Self-referring nests will
       result in an error.

    root_servers

       root_servers: This is a special "dictionary" element that can have
       multiple elements, where a given element points to either an ip, or a
       pointer to an ipv4 alias. For example:

       root_servers["."] = "list_of_servers"

       In this example, "." indicates that this is a listing of root_servers
       that will resolve any name not otherwise listed as a root_servers
       entry.

       list_of_servers is a list of root name servers in the exact same format
       as ipv4_aliases.

       The root_servers dictionary array can have multiple elements. Like csv2
       elements, the names must be valid domain names that end with the '.'
       character. When there are multiple root_servers elements, the element
       with the most domain name labels that matches the end of the hostname
       one is searching for is used.

       For example, let us suppose we have the following root_servers entries:

       root_servers["."] = "198.41.0.4"
       root_servers["com."] = "192.5.6.30"
       root_servers["example.net."] = "10.1.2.3,10.2.3.4"

       In this example, we use use the name server with the IP 10.1.2.3 or
       10.2.3.4 to start resolving "www.example.net", the name server with the
       IP 192.5.6.30 to start resolving "www.google.com", and the name server
       with the IP 198.41.0.4 to start resolving "www.maradns.org".

       Note that, while ips in a listing of root name servers can have
       netmasks, the netmask portion is ignored.

       The root_servers should point to root servers. If one wishes to use
       MaraDNS as a forwarding name server, which forwards DNS requests on to
       another server, use the upstream_servers variable instead.

    upstream_servers

       This is identical to the root_servers variable (can have multiple
       elements, the elements are a list of ipv4_addresses, the variable is a
       dictionary variable, etc.), but is used when one wishes to use MaraDNS
       to query other recursive servers, instead of querying the actual root
       name servers for an answer.

       Note that one can not have both root_servers and upstream_servers set
       in a given mararc file; MaraDNS will return with a fatal error if one
       attempts to do this.

       Like root_servers, this is a dictionary variable that can have multiple
       elements. For example:

       upstream_servers["."] = "10.5.6.7"
       upstream_servers["cl."] = "10.2.19.83"

       Here, we use 10.2.19.83 to resolve host names that end in "cl", and
       10.5.6.7 to resolve all other host names.

NORMAL VARIABLE FORMAT

       Normal variables. These are variables that can only take a single
       value.

       The syntax of a normal variable is in the form

       name = "value"

       Where name is the name of the normal variable, and value is the value
       of the variable in question.

NORMAL VARIABLES

       Here is a listing of normal variables that MaraDNS uses:

    ipv4_bind_addresses

       ipv4_bind_addresses: The IP addresses to give the MaraDNS server.

       This accepts one or more ipv4 IPs in dotted-decimal (e.g. "127.0.0.1")
       notation, and specifies what IP addresses the MaraDNS server will
       listen on. Multiple bind addresses are separated with a comma, like
       this: "10.1.2.3, 10.1.2.4, 127.0.0.1"

    admin_acl

       This is a list of ip/netmask pairs that are allowed to get certain
       administrative information about MaraDNS, including:

       * The version number of MaraDNS running

       * The number of threads MaraDNS has

       * MaraDNS' internal timestamp value

       Note that this information is not available unless the mararc variable
       debug_msg_level is sufficiently high.  See the information on
       debug_msg_level below for details on this and on the TXT queries sent
       to get the above information.

    bind_address

       bind_address: The IP address to give the MaraDNS server.

       This accepts a single IP in dotted-decimal (e.g. "127.0.0.1") notation,
       and specifies what IP address the MaraDNS server will listen on. Note
       that ipv4_bind_addresses has the same functionality.  This name is
       included so that old MaraDNS configuration files will continue to work
       with new MaraDNS releases.

    bind_star_handling

       In the case where there is both a star record for a given name and
       recordtype, a non-star record with the same name but a different
       recordtype, and no record for the given name and recordtype, MaraDNS
       will usually return the star record. BIND, on the other hand, will
       return a "not there" reply.  In other words:

       * If a non-A record for foo.example.com exists

       * An A record for *.example.com exists

       * No A record for foo.example.com exists

       * And the user asks for the A record for foo.example.com

       * MaraDNS will usually return the A record attached to *.example.com

       * BIND, on the other hand, returns a "not there" for foo.example.com

       If the BIND behavior is desired, set bind_star_handling to 1.
       Otherwise, set this to 0. In MaraDNS 1.3, this has a default value of
       1.

       In addition, if there is a star record that could match any given
       record type, when bind_star_handling is 1, it makes sure that MaraDNS
       does not incorrectly return a NXDOMAIN (RFC 4074 section 4.2).

       Also, if bind_star_handling has a value of 2, MaraDNS will handle the
       following case exactly as per section 4.3.3 of RFC1034:

       * If a record for foo.example.com exists

       * An A record for *.example.com exists

       * And the user asks for the A record for bar.foo.example.com

       * MaraDNS will usually return the A record attached to *.example.com

       * RFC1034 section 4.3.3 says one should return a NXDOMAIN.

       MaraDNS will exit with a fatal error if bind_star_handling has any
       value besides 0, 1, or 2.

    chroot_dir

       chroot_dir: The directory MaraDNS chroots to

       This accepts a single value: The full path to the directory to use as a
       chroot jail.

       Note that csv1 zone files are read after the chroot operation.  Hence,
       the chroot jail needs to have any and all zone files that MaraDNS will
       load.

    csv2_default_zonefile

       This is a special zone file that allows there to be stars at the end of
       hostnames. This file is similar to a normal csv2 zone file, but has the
       following features and limitations:

       * Stars are allowed at the end of hostnames

       * A SOA record is mandatory

       * NS records are mandatory

       * Neither CNAME, FQDN4, nor FQDN6 records are permitted in the zone
         file

       * Delegation NS records are not permitted in the zone file

       * Default zonefiles may not be transferred via zone transfer

       * Both recursion and default zonefiles may not be enabled at the same
         time

    csv2_synthip_list

       Sometimes the IP list of nameservers will be different than the
       nameservers one is bound to. This allows the synthetic nameserver list
       to have different IPs.

       Note that this may act in an unexpected manner if routable and non-
       routable (localhost and RFC1918) addresses are combined; in particular,
       a list with both routable and non-routable addresses will discard the
       non-routable IP addresses, and a list with rfc1918 and localhost
       addresses will discard the localhost addresses.

    csv2_tilde_handling

       How the csv2 zone file parser handles tildes (the ~ character) in csv2
       zone files. This is a numeric record, with a possible value between 0
       and 3 (four possible values). The way the csv2 parser acts at different
       csv2_tilde_handling levels:

       * 0) The csv2 parser behaves the same as it does in old MaraDNS
         releases: The tilde has no special significance to the parser.

       * 1) A tilde is not allowed anywhere in a csv2 zone file.

       * 2) A tilde is only allowed between records in a csv2 zone file. If a
         tilde is between the first record and the second record, a tilde is
         required to be between all records. Otherwise, a tilde is not allowed
         anywhere in a csv2 zone file. The first record can not be a TXT, WKS,
         or LOC record.

       * 3) A tilde is required to be between all records in a csv2 zone file.

       The default value for csv2_tilde_handling is 2; this allows
       compatibility with older zone files without tildes while allowing zone
       files to be updated to use the tilde to separate resource records.

    debug_msg_level

       This is a number indicating what level of information about a running
       MaraDNS process should be made public. When set to 0, no information
       will be made public.

       When set to one (the default), or higher, a Tversion.maradns. (TXT
       query for "version.maradns.") query will return the version number of
       MaraDNS.

       When set to two or higher, a Tnumthreads.maradns.  (TXT query for
       "numthreads.maradns.")  query will return the number of threads that
       MaraDNS is currently running, and a Tcache-elements.maradns.  query
       will return the number of elements in MaraDNS' cache.

       If MaraDNS is compiled with debugging information on, a
       Tmemusage.maradns. query will return the amount of memory MaraDNS has
       allocated. Note that the overhead for tracking memory usage is
       considerable and that compiling MaraDNS with "make debug" will greatly
       slow down MaraDNS.  A debug build of MaraDNS is not recommended for
       production use.

       When set to three or higher, a Ttimestamp.maradns. query will return,
       in seconds since the UNIX epoch, the timestamp for the system MaraDNS
       is running on.

    default_rrany_set

       This variable used to determine what kind of resource records were
       returned when an ANY query was sent. In MaraDNS, the data structures
       have since been revised to return any resource record type when an ANY
       query is sent; this variable does nothing, and is only here so that old
       MaraDNS mararc files will continue to work.  The only accepted values
       for this variable were 3 and 15.

    dns_port

       This is the port that MaraDNS listens on. This is usually 53 (the
       default value), but certain unusual MaraDNS setups (such as when
       resolving dangling CNAME records on but a single IP) may need to have a
       different value for this.

    dos_protection_level

       If this is set to a non-zero value, certain features of MaraDNS will be
       disabled in order to speed up MaraDNS' response time. This is designed
       for situations when a MaraDNS server is receiving a large number of
       queries, such as during a denial of service attack.

       This is a numeric variable; its default value is zero, indicating that
       all of MaraDNS' normal features are enabled. Higher numeric values
       disable more features:

       * A dos_protection_level between 1 and 78 (inclusive) disables getting
         MaraDNS status information remotely.

       * A dos_protection_level of 8 or above disables CNAME lookups.

       * A dos_protection_level or 12 or above disables delegation NS records.

       * A dos_protection_level of 14 or above disables ANY record processing.

       * A dos_protection_level of 18 or above disables star record processing
         at the beginning of hostnames (default zonefiles still work,
         however).

       * A dos_protection_level of 78 disables all authoritative processing,
         including default zonefiles; recursive lookups still work.

       The default level of dos_protection_level is 0 when there are one or
       more zonefiles; 78 when there are no zone files.

    ipv6_bind_address

       If MaraDNS is compiled with as an authoritative server, then this
       variable will tell MaraDNS which ipv6 address for the UDP server to;
       for this variable to be set, MaraDNS must be bound to at least one ipv4
       address.

    handle_noreply

       This is a numeric variable which determines how the recursive resolver
       informs the client that Mara was unable to contact any remote DNS
       servers when trying to resolve a given domain.  If this is set to 0, no
       response will be sent to the DNS client.  If this is set to 1, a
       "server fail" message will be sent to the DNS client.  If this is set
       to 2, either a "this host does not exist" message will be sent to the
       DNS client if notthere_ip is not set, or the IP specified in
       notthere_ip will be sent if set.  The default value for this is 1.

    hide_disclaimer

       If this is set to "YES", MaraDNS will not display the legal disclaimer
       when starting up.

    long_packet_ipv4

       This is a list of IPs which we will send UDP packets longer than the
       512 bytes RFC1035 permits if necessary. This is designed to allow
       zoneserver, when used send regular DNS packets over TCP, to receive
       packets with more data than can fit in a 512-byte DNS packet.

       This variable only functions if MaraDNS is compiled as an authoritative
       only server.

    maradns_uid

       maradns_uid: The numeric UID that MaraDNS will run as

       This accepts a single numerical value: The UID to run MaraDNS as.

       MaraDNS, as soon as possible drops root privileges, minimizing the
       damage a potential attacker can cause should there be a security
       problem with MaraDNS. This is the UID maradns becomes.

       The default UID is 99.

    maradns_gid

       maradns_gid: The numeric GID that MaraDNS will run as.

       This accepts a single numerical value: The GID to run MaraDNS as.

       The default GID is 99.

    maximum_cache_elements

       maximum_cache_elements: The maximum number of elements we can have in
       the cache of recursive queries.

       This cache of recursive queries is used to store entries we have
       previously obtained from recursive queries.

       If we approach this limit, the "custodian" kicks in to effect.  The
       custodian removes elements at random from the cache (8 elements removed
       per query) until we are at the 99% or so level again.

       The default value for this variable is 1024.

    maxprocs

       maxprocs: The maximum number of threads or processes that MaraDNS is
       allowed to run at the same time.

       This variable is used to minimize the impact on the server when MaraDNS
       is heavily loaded. When this number is reached, it is impossible for
       MaraDNS to spawn new threads/processes until the number of
       threads/processes is reduced.

       The default value for this variable is 64.

       The maximum value this can have is 500.

    max_ar_chain

       max_ar_chain: The maximum number of records to display if a record in
       the additional section (e.g., the IP of a NS server or the ip of a MX
       exchange) has more than one value.

       This is similar to max_chain, but applies to records in the
       "additional" (or AR) section.

       Due to limitations in the internal data structures that MaraDNS uses to
       store RRs, if this has a value besides one, round robin rotates of
       records are disabled.

       The default value for this variable is 1.

    max_chain

       max_chain: The maximum number of records to display in a chain of
       records.

       With DNS, it is possible to have more than one RR for a given domain
       label. For example, "example.com" can have, as the A record, a list of
       multiple ip addresses.

       This sets the maximum number of records MaraDNS will show for a single
       RR.

       MaraDNS normally round-robin rotates records. Hence, all records for a
       given DNS label (e.g. "example.com.") will be visible, although not at
       the same time if there are more records than the value allowed with
       max_chain

       The default value for this variable is 8.

    max_tcp_procs

       max_tcp_procs: The (optional) maximum number of processes the zone
       server is allowed to run.

       Sometimes, it is desirable to have a different number of maximum
       allowed tcp processes than maximum allowed threads. If this variable is
       not set, the maximum number of allowed tcp processes is "maxprocs".

    max_total

       max_total: The maximum number of records to show total for a given DNS
       request.

       This is the maximum total number of records that MaraDNS will make
       available in a DNS reply.

       The default value for this variable is 20.

    max_mem

       max_mem is the maximum amount of memory we allow MaraDNS to allocate,
       in bytes.

       The default value of this is to allocate 1 megabyte for MaraDNS'
       general use, and in addition, to allocate 1536 bytes for each element
       we can have in the cache or DNS record that we are authoritatively
       serving.

    min_ttl

       min_ttl: The minimum amount of time a resource record will stay in
       MaraDNS' cache, regardless of the TTL the remote server specifies.

       Setting this value changes the minimum amount of time MaraDNS'
       recursive server will keep a record in the cache. The value is in
       seconds.

       The default value of this is 300 (5 minutes); the minimum value for
       this is 180 (2 minutes).

    min_ttl_cname

       min_ttl_cname: The minimum amount of time a resource record will stay
       in MaraDNS' cache, regardless of the TTL the remote server specifies.

       Setting this value changes the amount of time a CNAME record stays in
       the cache. The value is in seconds.

       The default value for this is the value min_ttl has; the minimum value
       for this is 180 (2 minutes).

    min_visible_ttl

       min_visible_ttl: The minimum value that we will will show as the TTL
       (time to live) value for a resource record to other DNS servers and
       stub resolvers.  In other words, this is the minimum value we will ask
       other DNS server to cache (keep in their memory) a DNS resource record.

       The value is in seconds. The default value for this is 30; the minimum
       value this can have is 5. People running highly loaded MaraDNS servers
       may wish to increase this value to 3600 (one hour) in order to reduce
       the number of queries recursively processed by MaraDNS.

       As an aside, RFC1123 section 6.1.2.1 implies that zero-length TTL
       records should be passed on with a TTL of zero. This, unfortunately,
       breaks some stub resolvers (such as Mozilla's stub resolver).

    notthere_ip

       This parameter, if set, causes MaraDNS' recursive resolver to return a
       0-TTL synthetic IP for non-existent hostnames instead of a "this host
       does not exist" DNS reply. The IP returned is the value for this
       parameter.

       For example, if one wishes to send the IP 10.11.12.13 to clients
       whenever MaraDNS' recursive resolver gets a "this host does not exist"
       reply, set notthere_ip thusly:

       notthere_ip = "10.11.12.13"

       If one also wishes to have this IP returned when there is no reply from
       remote DNS servers, set handle_noreply thusly:

       handle_noreply = 2

       This parameter only affects the recursive resolver, and doesn't affect
       authoritative zones that MaraDNS serves. This parameter only affects A
       queries, and doesn't affect other DNS query types.

    random_seed_file

       random_seed_file: The file from which we read 16 bytes from to get the
       128-bit seed for the secure pseudo random number generator.

       The location of this file is relative to the root of the filesystem,
       not MaraDNS' chroot directory.

       This is ideally a file which is a good source of random numbers (e.g.
       /dev/urandom), but can also be a fixed file if your OS does not have a
       decent random number generator. In that case, make sure the contents of
       that file is random and with 600 perms, owned by root.  We read the
       file before dropping root privileges.

    recurse_delegation

       recurse_delegation: Whether to recurse in the case of us finding a NS
       delegation record, but the user/stub resolver sent a query that desires
       recursion. Before MaraDNS 1.3, this was the default behavior.

       When recurse_delegation has a value of 1, we recurse in this case.
       Otherwise, we do not.

       This parameter has a default value of 0.

    recurse_min_bind_port

       MaraDNS, by default, binds to a UDP port with a value between 15000 and
       19095 when making a recursive query. This variable, and the
       recurse_number_ports variable, allow this value to be changed.

       recurse_min_bind_port is the lowest port number that MaraDNS will bind
       to when making recursive queries. The default value for this is 15000.

    recurse_number_ports

       This determines the size of the port range MaraDNS will bind to when
       making recursive queries. MaraDNS, when making a recursive query, will
       locally bind to a port number between recurse_min_bin_port and
       recurse_min_bind_port + recurse_number_ports - 1.

       This number must be a power of 2 between 256 and 32768. In other words,
       this must have the value 256, 512, 1024, 2048, 4096, 8192, 16384, or
       32768. The default value for this is 4096.

       The sum of the values for recurse_min_bind_port + recurse_number_ports
       must fit within the 16-bit value used for UDP ports. In other words,
       these two parameters, added together, can not be greater than 65534.

    recursive_acl

       recursive_acl: List of ips allowed to perform recursive queries with
       the recursive portion of the MaraDNS server

       The format of this string is identical to the format of an ipv4_alias
       entry.

    remote_admin

       remote_admin: Whether we allow verbose_level to be changed after
       MaraDNS is started.

       If remote_admin is set to 1, and admin_acl is set, any and all IPs
       listed in admin_acl will be able to reset the value of verbose_level
       from any value between 0 and 9 via a TXT query in the form of
       5.verbose_level.maradns.  What this will do is set verbose_query to the
       value in the first digit of the query.

       This is useful when wishing to temporarily increase the verbose_level
       to find out why a given host name is not resolving, then decreasing
       verbose_level so as to minimize the size of MaraDNS' log.

    retry_cycles

       retry_cycles: The number of times the recursive resolver will try to
       contact all of the DNS servers to resolve a given name before giving
       up. This has a default value of 2.

    spammers

       spammers: A list of DNS servers which the recursive resolver will not
       query.

       This is mainly used to not allow spam-friendly domains to resolve,
       since spammers are starting to get in the habit of using spam-friendly
       DNS servers to resolve their domains, allowing them to hop from ISP to
       ISP.

       The format of this string is identical to the format of an ipv4_alias
       entry.

    synth_soa_origin

       When a CSV2 zone file doesn't have a SOA record in it, MaraDNS
       generates a SOA record on the fly. This variable determines the host
       name for the "SOA origin" (which is called the MNAME in RFC1035); this
       is the host name of the DNS server which has the "master copy" of a
       given DNS zone's file.

       This host name is in human-readable format without a trailing dot,
       e.g.:

       synth_soa_origin = "ns1.example.com"

       If this is not set, a synthetic SOA record will use the name of the
       zone for the SOA origin (MNAME) field.

    synth_soa_serial

       This determines whether we strictly follow RFC1912 section 2.2 with SOA
       serial numbers. If this is set to 1 (the default value), we do not
       strictly follow RFC1912 section 2.2 (the serial is a number, based on
       the timestamp of the zone file, that is updated every six seconds), but
       this makes it so that a serial number is guaranteed to be automatically
       updated every time one edits a zone file.

       If this is set to 2, the SOA serial number will be in YYYYMMDDHH
       format, where YYYY is the 4-digit year, MM is the 2-digit month, DD is
       the 2-digit day, and HH is the 2-digit hour of the time the zone file
       was last updated (GMT; localtime doesn't work in a chroot()
       environment). While this format is strictly RFC1912 compliant, the
       disadvantage is that more than one edit to a zone file in an hour will
       not update the serial number.

       I strongly recommend, unless it is extremely important to have a DNS
       zone that generates no warnings when tested at dnsreport.com, to have
       this set to 1 (the default value). Having this set to 2 can result in
       updated zone files not being seen by slave DNS servers.

       Note that synth_soa_serial can only have a value of 1 on the native
       Windows port.

    tcp_convert_acl

       This only applies to the zoneserver (general DNS-over-TCP) program.

       This is a list of IPs which are allowed to connect to the zoneserver
       and send normal TCP DNS requests. The zoneserver will convert TCP DNS
       requests in to UDP DNS requests, and send the UDP request in question
       to the server specified in tcp_convert_server.  Once it gets a reply
       from the UDP DNS server, it will convert the reply in to a TCP request
       and send the reply back to the original TCP client.

       Whether the RD (recursion desired) flag is set or not when converting a
       TCP DNS request in to a UDP DNS request is determined by whether the
       TCP client is on the recursive_acl list.

    tcp_convert_server

       This only applies to the zoneserver (general DNS-over-TCP) program.

       This is the UDP server which we send a query to when converting DNS TCP
       queries in to DNS UDP servers. Note that, while this value allows
       multiple IPs, all values except the first one are presently ignored.

    timeout_seconds

       This only applies when performing recursive lookups.

       The amount of time, in seconds, to wait for a reply from a remote DNS
       server before giving up and trying the next server on this list. The
       default value is 2 seconds.

       This is for setups where a recursive MaraDNS server is on a slow
       network which takes more than two seconds to send and receive a DNS
       packet.

       Note that, the larger this value is, the slower MaraDNS will process
       recursive queries when a DNS server is not responding to DNS queries.

    timestamp_type

       timestamp_type: The type of timestamp to display. The main purpose of
       this option is to suppress the output of timestamps. Since duende uses
       syslog() to output data, and since syslog() adds its own timestamp,
       this option should be set to 5 when maradns is invoked with the duende
       tool.

       This option also allows people who do not use the duende tool to view
       human-readable timestamps. This option only allows timestamps in GMT,
       due to issues with showing local times in a chroot() environment.

       This can have the following values:

       0   The string "Timestamp" followed by a UNIX timestamp

       1   Just the bare UNIX timestamp

       2   A GMT timestamp in the Spanish language

       3   A (hopefully) local timestamp in the Spanish language

       4   A timestamp using asctime(gmtime()); usually in the English
           language

       5   No timestamp whatsoever is shown (this is the best option when
           maradns is invoked with the duende tool).

       6   ISO GMT timestamp is shown

       7   ISO local timestamp is shown

       The default value for this variable is 5.

    upstream_port

       This is the port that MaraDNS' recursive resolver uses to contact other
       DNS servers. This is usually 53 (the default value), but certain
       unusual MaraDNS setups (such as when resolving dangling CNAME records
       on but a single IP) may need to have a different value for this.

    verbose_level

       verbose_level: The number of messages we log to stdout

       This can have five values:

       0   No messages except for the legal disclaimer and fatal parsing
           errors

       1   Only startup messages logged (Default level)

       2   Error queries logged

       3   All queries logged

       4   All actions adding and removing records from the cache logged

       The default value for this variable is 1.

    verbose_query

       verbose_query: Whether to verbosely output all DNS queries that the
       recursive DNS server receives. If this is set to 1, then all recursive
       queries sent to MaraDNS will be logged.

       This is mainly used for debugging.

    zone_transfer_acl

       zone_transfer_acl: List of ips allowed to perform zone transfers with
       the zone server

       The format of this string is identical to the format of an ipv4_alias
       entry.

EXAMPLE MARARC FILE

       # Example mararc file (unabridged version)

       # The various zones we support

       # We must initialize the csv2 hash, or MaraDNS will be unable to
       # load any csv2 zone files
       csv2 = {}

       # This is just to show the format of the file
       #csv2["example.com."] = "db.example.com"

       # The address this DNS server runs on.  If you want to bind
       # to multiple addresses, separate them with a comma like this:
       # "10.1.2.3,10.1.2.4,127.0.0.1"
       ipv4_bind_addresses = "127.0.0.1"
       # The directory with all of the zone files
       chroot_dir = "/etc/maradns"
       # The numeric UID MaraDNS will run as
       maradns_uid = 99
       # The (optional) numeric GID MaraDNS will run as
       # maradns_gid = 99
       # The maximum number of threads (or processes, with the zone server)
       # MaraDNS is allowed to run
       maxprocs = 96
       # It is possible to specify a different maximum number of processes that
       # the zone server can run.  If this is not set, the maximum number of
       # processes that the zone server can have defaults to the 'maxprocs' value
       # above
       # max_tcp_procs = 64

       # Normally, MaraDNS has some MaraDNS-specific features, such as DDIP
       # synthesizing, a special DNS query ("erre-con-erre-cigarro.maradns.org."
       # with a TXT query returns the version of MaraDNS that a server is
       # running), unique handling of multiple QDCOUNTs, etc.  Some people
       # might not like these features, so I have added a switch that lets
       # a sys admin disable all these features.  Just give "no_fingerprint"
       # a value of one here, and MaraDNS should be more or less
       # indistinguishable from a tinydns server.
       no_fingerprint = 0

       # Normally, MaraDNS only returns A and MX records when given a
       # QTYPE=* (all RR types) query.  Changing the value of default_rrany_set
       # to 15 causes MaraDNS to also return the NS and SOA records, which
       # some registrars require.  The default value of this is 3
       default_rrany_set = 3

       # These constants limit the number of records we will display, in order
       # to help keep packets 512 bytes or smaller.  This, combined with round_robin
       # record rotation, help to use DNS as a crude load-balancer.

       # The maximum number of records to display in a chain of records (list
       # of records) for a given host name
       max_chain = 8
       # The maximum number of records to display in a list of records in the
       # additional section of a query.  If this is any value besides one,
       # round robin rotation is disabled (due to limitations in the current
       # data structure MaraDNS uses)
       max_ar_chain = 1
       # The maximum number of records to show total for a given question
       max_total = 20

       # The number of messages we log to stdout
       # 0: No messages except for fatal parsing errors and the legal disclaimer
       # 1: Only startup messages logged (default)
       # 2: Error queries logged
       # 3: All queries logged (but not very verbosely right now)
       verbose_level = 1

       # Initialize the IP aliases, which are used by the list of root name servers,
       # the ACL for zone transfers, and the ACL of who gets to perform recursive
       # queries
       ipv4_alias = {}

       # Various sets of root name servers
       # Note: Netmasks can exist, but are ignored when specifying root name server

       # ICANN: the most common and most controversial root name server
       # http://www.icann.org
       # This list can be seen at http://www.root-servers.org/
       ipv4_alias["icann"]  = "198.41.0.4, 192.228.79.201, 192.33.4.12, 128.8.10.90,"
       ipv4_alias["icann"] += "192.203.230.10, 192.5.5.241, 192.112.36.4,"
       ipv4_alias["icann"] += "128.63.2.53, 192.36.148.17, 192.58.128.30,"
       ipv4_alias["icann"] += "193.0.14.129, 199.7.83.42, 202.12.27.33"

       # OpenNIC: http://www.opennic.unrated.net/
       # Current as of 2005/11/30; these servers change frequently so please
       # look at their web page
       ipv4_alias["opennic"]  = "157.238.46.24, 209.104.33.250, 209.104.63.249,"
       ipv4_alias["opennic"] += "130.94.168.216, 209.21.75.53, 64.114.34.119,"
       ipv4_alias["opennic"] += "207.6.128.246, 167.216.255.199, 62.208.181.95,"
       ipv4_alias["opennic"] += "216.87.153.98, 216.178.136.116"

       # End of list of root name server lists

       # Here is a ACL which restricts who is allowed to perform zone transfer from
       # the zoneserver program

       # Simplest form: 10.1.1.1/24 (IP: 10.1.1.1, 24 left bits in IP need to match)
       # and 10.100.100.100/255.255.255.224 (IP: 10.100.100.100, netmask
       # 255.255.255.224) are allowed to connect to the zone server
       # NOTE: The "maradns" program does not serve zones.  Zones are served
       # by the "zoneserver" program.
       #zone_transfer_acl = "10.1.1.1/24, 10.100.100.100/255.255.255.224"

       # More complex: We create two aliases: One called "office" and another
       # called "home".  We allow anyone in the office or at home to perform zone
       # transfers
       #ipv4_alias["office"] = "10.1.1.1/24"
       #ipv4_alias["home"] = "10.100.100.100/255.255.255.224"
       #zone_transfer_acl = "office, home"

       # More complex then the last example.  We have three employees,
       # Susan, Becca, and Mia, whose computers we give zone transfer rights to.
       # Susan and Becca are system administrators, and Mia is a developer.
       # They are all part of the company.  We give the entire company zone
       # transfer access
       #ipv4_alias["susan"]     = "10.6.7.8/32"  # Single IP allowed
       #ipv4_alias["becca"]     = "10.7.8.9"     # also a single IP
       #ipv4_alias["mia"]       = "10.8.9.10/255.255.255.255" # Also a single IP
       #ipv4_alias["sysadmins"] = "susan, becca"
       #ipv4_alias["devel"]     = "mia"
       #ipv4_alias["company"]   = "sysadmins, devel"
       # This is equivalent to the above line
       #ipv4_alias["company"]   = "susan, becca, mia"
       #zone_transfer_acl       = "company"

       # If you want to enable recursion on the loopback interface, uncomment
       # the relevant lines in the following section

       # Recursive ACL: Who is allowed to perform recursive queries.  The format
       # is identical to that of "zone_transfer_acl", including ipv4_alias support

       #ipv4_alias["localhost"] = "127.0.0.0/8"
       #recursive_acl = "localhost"

       # Random seed file: The file from which we read 16 bytes from to get the
       # 128-bit random Rijndael key.  This is ideally a file which is a good source
       # of random numbers, but can also be a fixed file if your OS does not have
       # a decent random number generator (make sure the contents of that file is
       # random and with 600 perms, owned by root, since we read the file *before*
       # dropping root privileges)

       #random_seed_file = "/dev/urandom"

       # The maximum number of elements we can have in the cache.  If we have more
       # elements in the cache than this amount, the "custodian" kicks in to effect,
       # removing elements not recently accessed from the cache (8 elements removed
       # per query) until we are at the 99% level or so again.

       #maximum_cache_elements = 1024

       # It is possible to change the minimal "time to live" for entries in the
       # cache; this is the minimum time that an entry will stay in the cache.
       # Value is in seconds; default is 300 (5 minutes)
       #min_ttl = 300
       # CNAME records generally take more effort to resolve in MaraDNS than
       # non-CNAME records; it is a good idea to make this higher then min_ttl
       # default value is to be the same as min_ttl
       #min_ttl_cname = 900

       # The root servers which we use when making recursive queries.

       # The following line must be uncommented to enable custom root servers
       # for recursive queries
       #root_servers = {}

       # You can choose which set of root servers to use.  Current values (set above)
       # are: icann, osrc, alternic, opennic,  pacificroot, irsc, tinc, and
       # superroot.
       #root_servers["."] = "icann"

       # If you prefer to contact other recursive DNS servers instead of the ICANN
       # root servers, this is done with the upstream_servers mararc variable:
       #upstream_servers["."] = "192.168.0.1, 192.168.0.2"

       # You can tell MaraDNS to *not* query certain DNS servers when in recursive
       # mode.  This is mainly used to not allow spam-friendly domains to resolve,
       # since spammers are starting to get in the habit of using spam-friendly
       # DNS servers to resolve their domains, allowing them to hop from ISP to
       # ISP.  The format of this is the same as for zone_transfer_acl and
       # recursive_acl

       # For example, at the time of this document (August 12, 2001), azmalink.net
       # is a known spam-friendly DNS provider (see doc/detailed/spammers/azmalink.net
       # for details.)  Note that this is based on IPs, and azmalink.net constantly
       # changes IPs (as they constantly have to change ISPs)
       # 2002/10/12: Azmalink changed ISP again, this reflect their current ISP
       ipv4_alias["azmalink"] = "12.164.194.0/24"

       # As of September 20, 2001, hiddenonline.net is a known spam-friendly
       # DNS provider (see doc/detailed/spammers/hiddenonline for details).
       ipv4_alias["hiddenonline"] = "65.107.225.0/24"
       spammers = "azmalink,hiddenonline"

       # It is also possible to change the maximum number of times MaraDNS will
       # follow a CNAME record or a NS record with a glue A record.  The default
       # value for this is ten.
       #max_glueless_level = 10
       # In addition, one can change the maximum number of total queries that
       # MaraDNS will perform to look up a host name.  The default value is 32.
       #max_queries_total = 32
       # In addition, one can change the amount of time that MaraDNS will wait
       # for a DNS server to respond before giving up and trying the next DNS
       # server on a list.  Note that, the larger this value is, the slower
       # MaraDNS will process recursive queries when a DNS server is not
       # responding to DNS queries.  The default value is two seconds.
       #timeout_seconds = 2

       # And that does it for the caching at this point

BUGS

       If one should declare the same the same index twice with a dictionary
       variable, MaraDNS will exit with a fatal error. This is because earlier
       versions of MaraDNS acted in a different manner than Python 2.3.3. With
       Python 2.3.3, the last declaration is used, while MaraDNS used to use
       the first declaration.

LEGAL DISCLAIMER

       THIS SOFTWARE IS PROVIDED BY THE AUTHORS ''AS IS'' AND ANY EXPRESS OR
       IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
       WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
       DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE FOR
       ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
       DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
       OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
       HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
       STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
       IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
       POSSIBILITY OF SUCH DAMAGE.