Provided by: dnsperf_2.9.0-1_amd64 bug


       dnsperf - test the performance of a DNS server


       dnsperf [-a local_addr] [-b bufsize] [-c clients] [-d datafile] [-D] [-e] [-E code:secret]
       [-f family] [-h] [-l limit] [-m mode] [-n runs_through_file] [-p port] [-q num_queries]
       [-Q max_qps] [-s server_addr] [-S stats_interval] [-t timeout] [-T threads] [-u] [-v] [-W]
       [-x local_port] [-y [alg:]name:secret] [-O option=value]


       dnsperf is a DNS server performance testing tool.  It is primarily intended for  measuring
       the  performance  of  authoritative  DNS  servers,  but  it can also be used for measuring
       caching server performance in  a  closed  laboratory  environment.   For  testing  caching
       servers resolving against the live Internet, the resperf program is preferred.

       It is recommended that dnsperf and the name server under test be run on separate machines,
       so that the CPU usage of dnsperf itself does not slow  down  the  name  server.   The  two
       machines  should be connected with a fast network, preferably a dedicated Gigabit Ethernet
       segment.  Testing through a router or firewall is not advisable.

   Configuring the name server
       If using dnsperf to test an authoritative server, the name server under test should be set
       up to serve one or more zones similar in size and number to what the server is expected to
       serve in production.

       Also, be sure to turn off recursion in the server's configuration (in  BIND  8/9,  specify
       "recursion  no;"  in  the  options block).  In BIND 8, you should also specify "fetch-glue
       no;"; otherwise the server may attempt to retrieve  glue  information  from  the  Internet
       during the test, slowing it down by an unpredictable factor.

   Constructing a query input file
       A  dnsperf input file should contain a large and realistic set of queries, on the order of
       ten thousand to a million.  The input file contains one line per query,  consisting  of  a
       domain  name  and  an  RR  type  name  separated  by  a  space.  The class of the query is
       implicitly IN.

       When measuring the performance serving non-terminal zones such as the root zone  or  TLDs,
       note  that  such  servers  spend  most  of  their  time  providing referral responses, not
       authoritative answers.  Therefore, a realistic input file might consist mostly of  queries
       for  type  A for names *below*, not at, the delegations present in the zone.  For example,
       when testing the performance of a server configured to be authoritative for the  top-level
       domain  "fi.",  which  contains delegations for domains like "" and "",
       the input file could contain lines like


       where the "www" prefix ensures that the server will respond with a referral.   Ideally,  a
       realistic  proportion of queries for nonexistent domains should be mixed in with those for
       existing ones, and the lines of the input file should be in a random order.

   Constructing a dynamic update input file
       To test dynamic update performance, dnsperf is run with the -u option, and the input  file
       is constructed of blocks of lines describing dynamic update messages.  The first line in a
       block contains the zone name:


       Subsequent lines contain prerequisites, if there are any.  Prerequisites can specify  that
       a  name  may  or  may not exist, an rrset may or may not exist, or an rrset exists and its
       rdata matches all specified rdata for that name and  type.   The  keywords  "require"  and
       "prohibit" are followed by the appropriate information.  All relative names are considered
       to be relative to the zone name.  The following lines show the 5 types of prerequisites.

              require a
              require a A
              require a A
              prohibit x
              prohibit x A

       Subsequent lines contain records to be added, records to be deleted, rrsets to be deleted,
       or  names  to  be deleted.  The keywords "add" or "delete" are followed by the appropriate
       information.  All relative names are considered to be relative  to  the  zone  name.   The
       following lines show the 4 types of updates.

              add x 3600 A
              delete y A
              delete z A
              delete w

       Each update message is terminated by a line containing the command:


   Running the tests
       When running dnsperf, a data file (the -d option) and server (the -s option) will normally
       be specified.  The output of dnsperf is mostly self-explanatory.   Pay  attention  to  the
       number  of  dropped  packets  reported  -  when  running  the  test  over a local Ethernet
       connection, it should be zero.  If one or more packets has been dropped, there  may  be  a
       problem  with  the  network  connection.   In  that case, the results should be considered
       suspect and the test repeated.

   Using DNS-over-HTTPS
       When using DNS-over-HTTPS you must set the -O doh-uri=... to something that works with the
       server  you're  sending to.  Also note that the value for maximum outstanding queries will
       be used to control the maximum concurrent streams within the HTTP/2 connection.


       -a local_addr
              Specifies the local address from which  to  send  requests.   The  default  is  the
              wildcard address.

       -b bufsize
              Sets  the  size  of  the  socket's  send and receive buffers, in kilobytes.  If not
              specified, the operating system's default is used.

       -c clients
              Act as multiple clients.  Requests are sent from multiple sockets.  The default  is
              to act as 1 client.

       -d datafile
              Specifies  the  input data file.  If not specified, dnsperf will read from standard

              Sets the DO (DNSSEC OK) bit [RFC3225] in  all  packets  sent.   This  also  enables
              EDNS0, which is required for DNSSEC.

              Enables EDNS0 [RFC2671], by adding an OPT record to all packets sent.

       -E code:value
              Add  an  EDNS  [RFC2671]  option  to  all packets sent, using the specified numeric
              option code and value expressed as a  a  hex-encoded  string.   This  also  enables

       -f family
              Specifies the address family used for sending DNS packets.  The possible values are
              "inet", "inet6", or "any".  If "any" (the default value) is specified, dnsperf will
              use  whichever  address  family is appropriate for the server it is sending packets

              Print a usage statement and exit.

       -l limit
              Specifies a time limit for the run, in seconds.  This may cause  the  input  to  be
              read multiple times, or only some of the input to be read.  The default behavior is
              to read the input once, and have no specific time limit.

       -n runs_through_file
              Run through the input file at most this many times.  If no time limit is  set,  the
              file  will  be  read exactly this number of times; if a time limit is set, the file
              may be read fewer times.

       -p port
              Sets the port on which the DNS packets are sent.  If not  specified,  the  standard
              DNS port (udp/tcp 53, DoT 853, DoH 443) is used.

       -q num_queries
              Sets  the  maximum  number  of  outstanding  requests.  When this value is reached,
              dnsperf will not send any more requests until  either  responses  are  received  or
              requests time out.  The default value is 100.

       -Q max_qps
              Limits the number of requests per second.  There is no default limit.

       -m mode
              Specifies  the  transport  mode  to  use, "udp", "tcp", "dot" or "doh".  Default is

       -s server_addr
              Specifies the name or address of the server to which requests will  be  sent.   The
              default is the loopback address,

       -S stats_interval
              If  this parameter is specified, a count of the number of queries per second during
              the interval will be printed out every stats_interval seconds.

       -t timeout
              Specifies the request timeout value, in seconds.  dnsperf will no longer wait for a
              response to a particular request after this many seconds have elapsed.  The default
              is 5 seconds.

       -T threads
              Run multiple client threads.  By default,  dnsperf  uses  one  thread  for  sending
              requests  and  one  thread  for  receiving responses.  If this option is specified,
              dnsperf will instead use N pairs of send/receive threads.

              Instructs dnsperf to send DNS dynamic update messages, rather  than  queries.   The
              format of the input file is different in this case; see the "Constructing a dynamic
              update input file" section for more details.

              Enables verbose mode.  The DNS RCODE of each response will be reported to  standard
              output  when  the response is received, as will the latency.  If a query times out,
              it will be reported with the special string "T" instead of a normal DNS RCODE.   If
              a  query  is  interrupted,  it  will  be  reported  with  the  special  string "I".
              Additional information regarding network readiness  and  congestion  will  also  be

              Log  warnings  and  errors  to  standard output instead of standard error making it
              easier for script, test and automation to capture all output.

       -x local_port
              Specifies the local port from which to send requests.  The default is the  wildcard
              port (0).

              If acting as multiple clients and the wildcard port is used, each client will use a
              different random port.  If a port is specified, the clients will  use  a  range  of
              ports starting with the specified one.

       -y [alg:]name:secret
              Add  a  TSIG  record  [RFC2845]  to  all packets sent, using the specified TSIG key
              algorithm, name and secret, where the algorithm defaults to hmac-md5 and the secret
              is  expressed  as  a  base-64  encoded string.  Available algorithms are: hmac-md5,
              hmac-sha1, hmac-sha224, hmac-sha256, hmac-sha384 and hmac-sha512.

       -O option=value
              Set an extended long option for various things  to  control  different  aspects  of
              testing or protocol modules, see EXTENDED OPTIONS for list of available options.


              The URI to use for DNS-over-HTTPS, default value is "https://localhost/dns-query".

              The  HTTP  method  to  use  when  querying  with  DNS-over-HTTPS,  default  is GET.
              Available methods are: GET, POST.

              Suppress various messages and warnings  that  may  be  shown  excessively  in  some
              situations,  such  as  socket  readiness  when  connecting  to a slow service.  Can
              suppress multiple types by listing them as a comma separated list.  Following  type
              are available.

              timeouts: Suppress messages about queries being timed out
              congestion: Suppress messages about network congestion
              sendfailed: Suppress messages about failure to send packets or if only parts of the
              packet were sent
              sockready: Suppress messages about socket readiness
              unexpected: Suppress messages about answers with an unexpected message ID

              This will limit the number of queries sent over a connection  before  triggering  a
              re-connection.  Once  re-connected  it  will reset the counter and continue sending
              queries until the limit is reached again, triggering another re-connection  and  so
              on.   Using  this option will also enable counting number of responses received for
              each connection and once the limit is reached for  sending  queries  it  will  wait
              until the same amount of responses has been received before re-connecting.  Waiting
              for responses may timeout and the timeout used for this is the same as specified by
              -t.  Note that this option is only useful for connection oriented protocols.




       Nominum, Inc.

       Maintained by DNS-OARC



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