ipset — administration tool for IP sets

       Jozsef Kadlecsik wrote ipset, which is based on ippool by Joakim  Axelsson,  Patrick  Schaaf  and  Martin
       Josefsson.
       Sven Wegener wrote the iptreemap type.

       Bugs? No, just funny features. :-) OK, just kidding...

       If you want to store same size subnets from a given network (say /24 blocks from a /8 network),  use  the
       bitmap:ip  set  type.   If  you  want to store random same size networks (say random /24 blocks), use the
       hash:ip set type. If you have got random size of netblocks, use hash:net.

       Matching on destination MAC addresses using the dst parameter of the set match netfilter  kernel  modules
       will  only  work if the destination MAC address is available in the packet at the given processing stage,
       that is, it only applies for incoming packets in the PREROUTING, INPUT and FORWARD  chains,  against  the
       MAC  address as originally found in the received packet (typically, one of the MAC addresses of the local
       host). This is not the destination MAC address a destination IP address resolves to,  after  routing.  If
       the MAC address is not available (e.g. in the OUTPUT chain), the packet will simply not match.

       Backward compatibility is maintained and old ipset syntax is still supported.

       The  iptree and iptreemap set types are removed: if you refer to them, they are automatically replaced by
       hash:ip type of sets.

ipset  is  used  to  set up, maintain and inspect so called IP sets in the Linux kernel. Depending on the
       type of the set, an IP set may store IP(v4/v6) addresses, (TCP/UDP) port  numbers,  IP  and  MAC  address
       pairs, IP address and port number pairs, etc. See the set type definitions below.

       Iptables  matches  and  targets  referring to sets create references, which protect the given sets in the
       kernel. A set cannot be destroyed while there is a single reference pointing to it.

       Various error messages are printed to standard error.  The exit code is 0 for correct functioning.

       Zero valued set entries cannot be used with hash methods. Zero protocol value with ports cannot be used.

timeout
       All  set  types supports the optional timeout parameter when creating a set and adding entries. The value
       of the timeout parameter for the create command means the default timeout  value  (in  seconds)  for  new
       entries.  If  a  set is created with timeout support, then the same timeout option can be used to specify
       non-default timeout values when adding entries. Zero timeout value means the entry is added permanent  to
       the  set.   The timeout value of already added elements can be changed by re-adding the element using the
       -exist option. The largest possible timeout value is 2147483 (in seconds). Example:

              ipset create test hash:ip timeout 300

              ipset add test 192.168.0.1 timeout 60

              ipset -exist add test 192.168.0.1 timeout 600

       When listing the set, the number of entries printed in the header might be larger than the listed  number
       of  entries  for  sets  with  the  timeout  extensions:  the number of entries in the set is updated when
       elements added/deleted to the set and periodically when  the  garbage  collector  evicts  the  timed  out
       entries.

   counters,packets,bytes
       All  set  types support the optional counters option when creating a set. If the option is specified then
       the set is created with packet and byte counters per element support. The packet and  byte  counters  are
       initialized  to  zero  when  the  elements  are (re-)added to the set, unless the packet and byte counter
       values are explicitly specified by the packets and bytes options. An example when an element is added  to
       a set with non-zero counter values:

              ipset create foo hash:ip counters

              ipset add foo 192.168.1.1 packets 42 bytes 1024

   comment
       All set types support the optional comment extension.  Enabling this extension on an ipset enables you to
       annotate  an  ipset  entry with an arbitrary string. This string is completely ignored by both the kernel
       and ipset itself and is purely for providing a convenient means to document the  reason  for  an  entry's
       existence.  Comments  must  not  contain  any  quotation  marks and the usual escape character (\) has no
       meaning. For example, the following shell command is illegal:

              ipset add foo 1.1.1.1 comment "this comment is \"bad\""

       In the above, your shell will of course escape the quotation marks and ipset will see the quote marks  in
       the  argument  for  the comment, which will result in a parse error.  If you are writing your own system,
       you should avoid creating comments containing a quotation mark if you do not want to break  "ipset  save"
       and  "ipset restore", nonetheless, the kernel will not stop you from doing so. The following is perfectly
       acceptable:

              ipset create foo hash:ip comment

              ipset add foo 192.168.1.1/24 comment "allow access to SMB share on \\\\fileserv\\"

              the above would appear as: "allow access to SMB share on \\fileserv\"

   skbinfo,skbmark,skbprio,skbqueue
       All set types support the optional skbinfo extension. This extension allows you  to  store  the  metainfo
       (firewall  mark,  tc  class  and  hardware  queue) with every entry and map it to packets by usage of SET
       netfilter target with --map-set option.  skbmark option format: MARK or MARK/MASK, where  MARK  and  MASK
       are 32bit hex numbers with 0x prefix. If only mark is specified mask 0xffffffff are used.  skbprio option
       has  tc  class  format:  MAJOR:MINOR,  where major and minor numbers are hex without 0x prefix.  skbqueue
       option is just decimal number.

              ipset create foo hash:ip skbinfo

              ipset add foo 192.168.0.1 skbmark 0x1111/0xff00ffff skbprio 1:10 skbqueue 10

   hashsize
       This parameter is valid for the create command of all hash type sets.  It defines the initial  hash  size
       for  the  set,  default is 1024. The hash size must be a power of two, the kernel automatically rounds up
       non power of two hash sizes to the first correct value.  Example:

              ipset create test hash:ip hashsize 1536

   maxelem
       This parameter is valid for the create command of all hash type sets.  It defines the maximal  number  of
       elements which can be stored in the set, default 65536.  Example:

              ipset create test hash:ip maxelem 2048

   bucketsize
       This parameter is valid for the create command of all hash type sets.  It specifies the maximal number of
       elements  which  can be stored in a hash bucket. Possible values are any even number between 2-14 and the
       default is 14. Setting the value lower forces ipset to create larger hashes which  consumes  more  memory
       but gives more speed at matching in the set.  Example:

              ipset create test hash:ip bucketsize 2

   family{inet|inet6}
       This parameter is valid for the create command of all hash type sets except for hash:mac.  It defines the
       protocol family of the IP addresses to be stored in the set. The default is inet, i.e IPv4.  For the inet
       family one can add or delete multiple entries by specifying a range or a network of IPv4 addresses in the
       IP address part of the entry:

       ipaddr := { ip | fromaddr-toaddr | ip/cidr }

       netaddr := { fromaddr-toaddr | ip/cidr }

       Example:

              ipset create test hash:ip family inet6

   nomatch
       The hash set types which can store net type of data (i.e. hash:*net*) support the optional nomatch option
       when adding entries. When matching elements in the set, entries marked as nomatch are skipped as if those
       were not added to the set, which makes possible to build up sets with exceptions. See the example at hash
       type hash:net below.

       When  elements  are  tested  by ipset, the nomatch flags are taken into account. If one wants to test the
       existence of an element marked with nomatch in a set, then the flag must be specified too.

   forceadd
       All hash set types support the optional forceadd parameter when creating a set.  When sets  created  with
       this option become full the next addition to the set may succeed and evict a random entry from the set.

              ipset create foo hash:ip forceadd

   wildcard
       This flag is valid when adding elements to a hash:net,iface set. If the flag is set, then prefix matching
       is  used  when  comparing  with this element. For example, an element containing the interface name "eth"
       will match any name with that prefix.

       A set type comprises of the storage method by which the data is stored and the  data  type(s)  which  are
       stored in the set. Therefore the TYPENAME parameter of the create command follows the syntax

       TYPENAME := method:datatype[,datatype[,datatype]]

       where the current list of the methods are bitmap, hash, and list and the possible data types are ip, net,
       mac, port and iface.  The dimension of a set is equal to the number of data types in its type name.

       When  adding, deleting or testing entries in a set, the same comma separated data syntax must be used for
       the entry parameter of the commands, i.e

              ipset add foo ipaddr,portnum,ipaddr

       If host names or service names with dash in the name are used instead of IP addresses or service numbers,
       then the host name or service name must be enclosed in square brackets. Example:

              ipset add foo [test-hostname],[ftp-data]

       In the case of host names the DNS resolver is called internally by ipset but if it  returns  multiple  IP
       addresses, only the first one is used.

       The  bitmap and list types use a fixed sized storage. The hash types use a hash to store the elements. In
       order to avoid clashes in the hash, a limited number of chaining, and if that is exhausted, the  doubling
       of  the  hash  size  is performed when adding entries by the ipset command. When entries added by the SET
       target of iptables/ip6tables, then the hash size is fixed and the set won't be duplicated,  even  if  the
       new entry cannot be added to the set.

Istandontheshouldersofgiants.

Jozsef Kadlecsik                                  Jun 25, 2015                                          IPSET(8)

       ipset — administration tool for IP sets

       The options that are recognized by ipset can be divided into several different groups.

   COMMANDS
       These options specify the desired action to perform.  Only one of them can be specified  on  the  command
       line  unless  otherwise specified below.  For all the long versions of the command names, you need to use
       only enough letters to ensure that ipset can differentiate it from all other commands. The  ipset  parser
       follows the order here when looking for the shortest match in the long command names.

       n, createSETNAMETYPENAME [ CREATE-OPTIONS ]
              Create  a  set  identified  with  setname  and  specified type. The type may require type specific
              options. If the -exist option is specified, ipset ignores the error otherwise raised when the same
              set (setname and create parameters are identical) already exists.

       addSETNAMEADD-ENTRY [ ADD-OPTIONS ]
              Add a given entry to the set. If the -exist option  is  specified,  ipset  ignores  if  the  entry
              already added to the set.

       delSETNAMEDEL-ENTRY [ DEL-OPTIONS ]
              Delete  an  entry  from  a  set. If the -exist option is specified and the entry is not in the set
              (maybe already expired), then the command is ignored.

       testSETNAMETEST-ENTRY [ TEST-OPTIONS ]
              Test whether an entry is in a set or not. Exit status number is zero if the tested entry is in the
              set and nonzero if it is missing from the set.

       x, destroy [ SETNAME ]
              Destroy the specified set or all the sets if none is given.

              If the set has got reference(s), nothing is done and no set destroyed.

       list [ SETNAME ] [ OPTIONS ]
              List the header data and the entries for the specified set, or for all sets if none is given.  The
              -resolve  option can be used to force name lookups (which may be slow). When the -sorted option is
              given, the entries are listed/saved sorted (which may be slow).  The option -output can be used to
              control the format of the listing: plain, save, xml or json.  (The  default  is  plain.)   If  the
              option -name is specified, just the names of the existing sets are listed. If the option -terse is
              specified,  just the set names and headers are listed. The output is printed to stdout, the option
              -file can be used to specify a filename instead of stdout.

       save [ SETNAME ]
              Save the given set, or all sets if none is given to stdout in a format that restore can read.  The
              option -file can be used to specify a filename instead of stdout.

       restore
              Restore  a saved session generated by save.  The saved session can be fed from stdin or the option
              -file can be used to specify a filename instead of stdin.

              Please note, existing sets and elements are not erased by  restore  unless  specified  so  in  the
              restore  file.  All  commands  are allowed in restore mode except list, help, version, interactive
              mode and restore itself.

       flush [ SETNAME ]
              Flush all entries from the specified set or flush all sets if none is given.

       e, renameSETNAME-FROMSETNAME-TO
              Rename a set. Set identified by SETNAME-TO must not exist.

       w, swapSETNAME-FROMSETNAME-TO
              Swap the content of two sets, or in another words, exchange the name of  two  sets.  The  referred
              sets must exist and compatible type of sets can be swapped only.

       help [ TYPENAME ]
              Print help and set type specific help if TYPENAME is specified.

       version
              Print program version.

       -      If  a  dash  is specified as command, then ipset enters a simple interactive mode and the commands
              are read from the  standard  input.   The  interactive  mode  can  be  finished  by  entering  the
              pseudo-command quit.

   OTHEROPTIONS
       The following additional options can be specified. The long option names cannot be abbreviated.

       -!, -exist
              Ignore  errors  when  exactly  the  same  set  is to be created or already added entry is added or
              missing entry is deleted.

       -o, -output { plain | save | xml | json }
              Select the output format to the list command.

       -q, -quiet
              Suppress any output to stdout and stderr.  ipset will still exit with error if it cannot continue.

       -r, -resolve
              When listing sets, enforce name lookup. The program will try to display the IP entries resolved to
              host names which requires slow DNS lookups.

       -s, -sorted
              Sorted output. When listing or saving sets, the entries are listed sorted.

       -n, -name
              List just the names of the existing sets, i.e. suppress listing of set headers and members.

       -t, -terse
              List the set names and headers, i.e. suppress listing of set members.

       -f, -filefilename
              Specify a filename to print into instead of stdout (list or save commands) or read from instead of
              stdin (restore command).

iptables(8), ip6tables(8) iptables-extensions(8)

bitmap:ip
       The bitmap:ip set type uses a memory range to store either IPv4 host (default) or IPv4 network addresses.
       A bitmap:ip type of set can store up to 65536 entries.

       CREATE-OPTIONS := rangefromip-toip|ip/cidr [ netmaskcidr ] [ timeoutvalue ] [ counters ] [ comment ] [
       skbinfo ]

       ADD-ENTRY := { ip | fromip-toip | ip/cidr }

       ADD-OPTIONS := [ timeoutvalue ] [ packetsvalue ] [ bytesvalue ] [ commentstring ] [ skbmarkvalue ] [
       skbpriovalue ] [ skbqueuevalue ]

       DEL-ENTRY := { ip | fromip-toip | ip/cidr }

       TEST-ENTRY := ip

       Mandatory create options:

       rangefromip-toip|ip/cidr
              Create the set from the specified inclusive address range expressed in an IPv4  address  range  or
              network. The size of the range (in entries) cannot exceed the limit of maximum 65536 elements.

       Optional create options:

       netmaskcidr
              When the optional netmask parameter specified, network addresses will be stored in the set instead
              of  IP  host  addresses. The cidr prefix value must be between 1-32.  An IP address will be in the
              set if the network address, which is resulted by masking the address with the  specified  netmask,
              can be found in the set.

       The bitmap:ip type supports adding or deleting multiple entries in one command.

       Examples:

              ipset create foo bitmap:ip range 192.168.0.0/16

              ipset add foo 192.168.1/24

              ipset test foo 192.168.1.1

   bitmap:ip,mac
       The  bitmap:ip,mac  set  type  uses a memory range to store IPv4 and a MAC address pairs. A bitmap:ip,mac
       type of set can store up to 65536 entries.

       CREATE-OPTIONS := rangefromip-toip|ip/cidr [ timeoutvalue ] [ counters ] [ comment ] [ skbinfo ]

       ADD-ENTRY := ip[,macaddr]

       ADD-OPTIONS := [ timeoutvalue ] [ packetsvalue ] [ bytesvalue ] [ commentstring ] [ skbmarkvalue ] [
       skbpriovalue ] [ skbqueuevalue ]

       DEL-ENTRY := ip[,macaddr]

       TEST-ENTRY := ip[,macaddr]

       Mandatory options to use when creating a bitmap:ip,mac type of set:

       rangefromip-toip|ip/cidr
              Create the set from the specified inclusive address range expressed in an IPv4  address  range  or
              network. The size of the range cannot exceed the limit of maximum 65536 entries.

       The  bitmap:ip,mac  type  is  exceptional  in  the  sense  that  the  MAC  part  can  be  left  out  when
       adding/deleting/testing entries in the set. If we add an entry without the MAC  address  specified,  then
       when  the  first  time the entry is matched by the kernel, it will automatically fill out the missing MAC
       address with the MAC address from the packet. The source MAC address is used if the entry matched due  to
       a  src  parameter  of  the  set match, and the destination MAC address is used if available and the entry
       matched due to a dst parameter.  If the entry was specified with a timeout value, the  timer  starts  off
       when the IP and MAC address pair is complete.

       The  bitmap:ip,mac  type of sets require two src/dst parameters of the set match and SET target netfilter
       kernel modules. For matches on destination MAC addresses, see COMMENTS below.

       Examples:

              ipset create foo bitmap:ip,mac range 192.168.0.0/16

              ipset add foo 192.168.1.1,12:34:56:78:9A:BC

              ipset test foo 192.168.1.1

   bitmap:port
       The bitmap:port set type uses a memory range to store port numbers and such a set can store up  to  65536
       ports.

       CREATE-OPTIONS := rangefromport-toport[timeoutvalue ] [ counters ] [ comment ] [ skbinfo ]

       ADD-ENTRY := { [proto:]port | [proto:]fromport-toport }

       ADD-OPTIONS := [ timeoutvalue ] [ packetsvalue ] [ bytesvalue ] [ commentstring ] [ skbmarkvalue ] [
       skbpriovalue ] [ skbqueuevalue ]

       DEL-ENTRY := { [proto:]port | [proto:]fromport-toport }

       TEST-ENTRY := [proto:]port

       Mandatory options to use when creating a bitmap:port type of set:

       range[proto:]fromport-toport
              Create the set from the specified inclusive port range.

       The  set  match  and  SET target netfilter kernel modules interpret the stored numbers as TCP or UDP port
       numbers.

       proto only needs to be specified if a service name is used and that name does not exist as a TCP service.
       The protocol is never stored in the set, just the port number of the service.

       Examples:

              ipset create foo bitmap:port range 0-1024

              ipset add foo 80

              ipset test foo 80

              ipset del foo udp:[macon-udp]-[tn-tl-w2]

   hash:ip
       The hash:ip set type uses a hash to store IP host addresses (default) or network addresses.  Zero  valued
       IP address cannot be stored in a hash:ip type of set.

       CREATE-OPTIONS := [ family { inet | inet6 } ] [ hashsizevalue ] [ maxelemvalue ] [ bucketsizevalue ] [
       netmaskcidr ] [ bitmaskmask ] [ timeoutvalue ] [ counters ] [ comment ] [ skbinfo ]

       ADD-ENTRY := ipaddrADD-OPTIONS := [ timeoutvalue ] [ packetsvalue ] [ bytesvalue ] [ commentstring ] [ skbmarkvalue ] [
       skbpriovalue ] [ skbqueuevalue ]

       DEL-ENTRY := ipaddrTEST-ENTRY := ipaddr

       Optional create options:

       netmaskcidr
              When the optional netmask parameter specified, network addresses will be stored in the set instead
              of  IP  host  addresses. The cidr prefix value must be between 1-32 for IPv4 and between 1-128 for
              IPv6. An IP address will be in the set if the network address, which is resulted  by  masking  the
              address with the netmask, can be found in the set.  Examples:

              ipset create foo hash:ip netmask 30

              ipset add foo 192.168.1.0/24

              ipset test foo 192.168.1.2

       bitmaskmask
              This works similar to netmask but it will accept any valid IPv4/v6 address. It does not have to be
              a valid netmask.

   hash:mac
       The hash:mac set type uses a hash to store MAC addresses. Zero valued MAC addresses cannot be stored in a
       hash:mac type of set. For matches on destination MAC addresses, see COMMENTS below.

       CREATE-OPTIONS  := [ hashsizevalue ] [ maxelemvalue ] [ bucketsizevalue ] [ timeoutvalue ] [ counters
       ] [ comment ] [ skbinfo ]

       ADD-ENTRY := macaddrADD-OPTIONS := [ timeoutvalue ] [ packetsvalue ] [ bytesvalue ] [ commentstring ] [ skbmarkvalue ] [
       skbpriovalue ] [ skbqueuevalue ]

       DEL-ENTRY := macaddrTEST-ENTRY := macaddr

       Examples:

              ipset create foo hash:mac

              ipset add foo 01:02:03:04:05:06

              ipset test foo 01:02:03:04:05:06

   hash:ip,mac
       The hash:ip,mac set type uses a hash to store IP and a MAC  address  pairs.  Zero  valued  MAC  addresses
       cannot  be  stored  in  a hash:ip,mac type of set. For matches on destination MAC addresses, see COMMENTS
       below.

       CREATE-OPTIONS := [ family { inet | inet6 } ] [ hashsizevalue ] [ maxelemvalue ] [ bucketsizevalue ] [
       timeoutvalue ] [ counters ] [ comment ] [ skbinfo ]

       ADD-ENTRY := ipaddr,macaddrADD-OPTIONS := [ timeoutvalue ] [ packetsvalue ] [ bytesvalue ] [ commentstring ] [ skbmarkvalue ] [
       skbpriovalue ] [ skbqueuevalue ]

       DEL-ENTRY := ipaddr,macaddrTEST-ENTRY := ipaddr,macaddr

       Examples:

              ipset create foo hash:ip,mac

              ipset add foo 1.1.1.1,01:02:03:04:05:06

              ipset test foo 1.1.1.1,01:02:03:04:05:06

   hash:net
       The hash:net set type uses a hash to store different sized IP network addresses.   Network  address  with
       zero prefix size cannot be stored in this type of sets.

       CREATE-OPTIONS := [ family { inet | inet6 } ] [ hashsizevalue ] [ maxelemvalue ] [ bucketsizevalue ] [
       timeoutvalue ] [ counters ] [ comment ] [ skbinfo ]

       ADD-ENTRY := netaddrADD-OPTIONS  :=  [  timeoutvalue  ]  [ nomatch ] [ packetsvalue ] [ bytesvalue ] [ commentstring ] [
       skbmarkvalue ] [ skbpriovalue ] [ skbqueuevalue ]

       DEL-ENTRY := netaddrTEST-ENTRY := netaddr

       where netaddr := ip[/cidr]

       When adding/deleting/testing entries, if the cidr prefix parameter is not specified, then the host prefix
       value is assumed. When adding/deleting entries,  the  exact  element  is  added/deleted  and  overlapping
       elements  are  not  checked  by  the kernel.  When testing entries, if a host address is tested, then the
       kernel tries to match the host address  in  the  networks  added  to  the  set  and  reports  the  result
       accordingly.

       From  the  set netfilter match point of view the searching for a match always  starts  from  the smallest
       size  of netblock (most specific prefix) to the largest one (least specific prefix)  added  to  the  set.
       When  adding/deleting IP addresses  to the set by the SET netfilter target, it  will  be added/deleted by
       the most specific prefix which can be found in  the set, or by the host prefix value if the set is empty.

       The lookup time grows linearly with the number of the different prefix values added to the set.

       Example:

              ipset create foo hash:net

              ipset add foo 192.168.0.0/24

              ipset add foo 10.1.0.0/16

              ipset add foo 192.168.0/24

              ipset add foo 192.168.0/30 nomatch

       When  matching  the  elements  in  the  set  above,  all  IP  addresses  will  match  from  the  networks
       192.168.0.0/24, 10.1.0.0/16 and 192.168.0/24 except the ones from 192.168.0/30.

   hash:net,net
       The hash:net,net set type uses a hash to store pairs of different sized IP network addresses.   Bear   in
       mind   that  the  first parameter has precedence over the second, so a nomatch entry could be potentially
       be ineffective if a more specific first parameter existed with  a  suitable  second  parameter.   Network
       address with zero prefix size cannot be stored in this type of set.

       CREATE-OPTIONS := [ family { inet | inet6 } ] [ hashsizevalue ] [ maxelemvalue ] [ bucketsizevalue ] [
       netmaskcidr ] [ bitmaskmask ] [ timeoutvalue ] [ counters ] [ comment ] [ skbinfo ]

       ADD-ENTRY := netaddr,netaddrADD-OPTIONS  :=  [  timeoutvalue  ]  [ nomatch ] [ packetsvalue ] [ bytesvalue ] [ commentstring ] [
       skbmarkvalue ] [ skbpriovalue ] [ skbqueuevalue ]

       DEL-ENTRY := netaddr,netaddrTEST-ENTRY := netaddr,netaddr

       where netaddr := ip[/cidr]

       When adding/deleting/testing entries, if the cidr prefix parameter is not specified, then the host prefix
       value is assumed. When adding/deleting entries,  the  exact  element  is  added/deleted  and  overlapping
       elements  are  not  checked  by  the kernel.  When testing entries, if a host address is tested, then the
       kernel tries to match the host address  in  the  networks  added  to  the  set  and  reports  the  result
       accordingly.

       From  the  set netfilter match point of view the searching for a match always  starts  from  the smallest
       size  of netblock (most specific prefix) to the largest one (least specific prefix) with the first  param
       having  precedence.  When  adding/deleting IP addresses  to the set by the SET netfilter target, it  will
       be  added/deleted  by  the most specific prefix which can be found in the set,  or  by  the  host  prefix
       value if the set is empty.

       The  lookup  time  grows  linearly  with  the  number  of  the different prefix values added to the first
       parameter of the set. The number of secondary prefixes further increases this as the  list  of  secondary
       prefixes is traversed per primary prefix.

       Optional create options:

       netmaskcidr
              When the optional netmask parameter specified, network addresses will be stored in the set instead
              of  IP  host  addresses. The cidr prefix value must be between 1-32 for IPv4 and between 1-128 for
              IPv6. An IP address will be in the set if the network address, which is resulted  by  masking  the
              address with the netmask, can be found in the set.

       bitmaskmask
              This works similar to netmask but it will accept any valid IPv4/v6 address. It does not have to be
              a valid netmask.

       Example:

              ipset create foo hash:net,net

              ipset add foo 192.168.0.0/24,10.0.1.0/24

              ipset add foo 10.1.0.0/16,10.255.0.0/24

              ipset add foo 192.168.0/24,192.168.54.0-192.168.54.255

              ipset add foo 192.168.0/30,192.168.64/30 nomatch

       When  matching  the  elements  in  the  set  above,  all  IP  addresses  will  match  from  the  networks
       192.168.0.0/24<->10.0.1.0/24, 10.1.0.0/16<->10.255.0.0/24 and 192.168.0/24<->192.168.54.0/24  except  the
       ones from 192.168.0/30<->192.168.64/30.

   hash:ip,port
       The  hash:ip,port  set  type  uses  a hash to store IP address and port number pairs.  The port number is
       interpreted together with a protocol (default TCP) and zero protocol number cannot be used.

       CREATE-OPTIONS := [ family { inet | inet6 } ] [ hashsizevalue ] [ maxelemvalue ] [ bucketsizevalue ] [
       netmaskcidr ] [ bitmaskmask ] [ timeoutvalue ] [ counters ] [ comment ] [ skbinfo ]

       ADD-ENTRY := ipaddr,[proto:]portADD-OPTIONS := [ timeoutvalue ] [ packetsvalue ] [ bytesvalue ] [ commentstring ] [ skbmarkvalue ] [
       skbpriovalue ] [ skbqueuevalue ]

       DEL-ENTRY := ipaddr,[proto:]portTEST-ENTRY := ipaddr,[proto:]port

       The [proto:]port part of the elements may be expressed in the following forms, where the range variations
       are valid when adding or deleting entries:

       portname[-portname]
              TCP port or range of ports expressed in TCP portname identifiers from /etc/servicesportnumber[-portnumber]
              TCP port or range of ports expressed in TCP port numbers

       tcp|sctp|udp|udplite:portname|portnumber[-portname|portnumber]
              TCP, SCTP, UDP or UDPLITE port or port range expressed in port name(s) or port number(s)

       icmp:codename|type/code
              ICMP codename or type/code. The supported ICMP codename identifiers can always be  listed  by  the
              help command.

       icmpv6:codename|type/code
              ICMPv6  codename  or  type/code. The supported ICMPv6 codename identifiers can always be listed by
              the help command.

       proto:0
              All other protocols, as an identifier from /etc/protocols or number. The pseudo port  number  must
              be zero.

       The  hash:ip,port  type  of  sets  require  two src/dst parameters of the set match and SET target kernel
       modules.

       Optional create options:

       netmaskcidr
              When the optional netmask parameter specified, network addresses will be stored in the set instead
              of IP host addresses. The cidr prefix value must be between 1-32 for IPv4 and  between  1-128  for
              IPv6.  An  IP  address will be in the set if the network address, which is resulted by masking the
              address with the netmask, can be found in the set.

       bitmaskmask
              This works similar to netmask but it will accept any valid IPv4/v6 address. It does not have to be
              a valid netmask.

       Examples:

              ipset create foo hash:ip,port

              ipset add foo 192.168.1.0/24,80-82

              ipset add foo 192.168.1.1,udp:53

              ipset add foo 192.168.1.1,vrrp:0

              ipset test foo 192.168.1.1,80

   hash:net,port
       The hash:net,port set type uses a hash to store different sized IP network address and  port  pairs.  The
       port  number  is  interpreted  together  with a protocol (default TCP) and zero protocol number cannot be
       used. Network address with zero prefix size is not accepted either.

       CREATE-OPTIONS := [ family { inet | inet6 } ] [ hashsizevalue ] [ maxelemvalue ] [ bucketsizevalue ] [
       timeoutvalue ] [ counters ] [ comment ] [ skbinfo ]

       ADD-ENTRY := netaddr,[proto:]portADD-OPTIONS := [ timeoutvalue ]  [ nomatch ] [ packetsvalue ] [ bytesvalue ]  [  commentstring  ]  [
       skbmarkvalue ] [ skbpriovalue ] [ skbqueuevalue ]

       DEL-ENTRY := netaddr,[proto:]portTEST-ENTRY := netaddr,[proto:]port

       where netaddr := ip[/cidr]

       For  the  netaddr part of the elements see the description at the hash:net set type. For the [proto:]port
       part of the elements see the description at the hash:ip,port set type.

       When adding/deleting/testing entries, if the cidr prefix parameter is not specified, then the host prefix
       value is assumed. When adding/deleting entries,  the  exact  element  is  added/deleted  and  overlapping
       elements  are  not  checked  by  the kernel.  When testing entries, if a host address is tested, then the
       kernel tries to match the host address  in  the  networks  added  to  the  set  and  reports  the  result
       accordingly.

       From  the set netfilter match point of view the searching for a  match always  starts  from  the smallest
       size  of netblock (most specific prefix) to the largest one (least specific prefix)  added  to  the  set.
       When  adding/deleting IP addresses  to the set by the SET netfilter target, it  will  be added/deleted by
       the most specific prefix which can be found in  the set, or by the host prefix value if the set is empty.

       The lookup time grows linearly with the number of the different prefix values added to the set.

       Examples:

              ipset create foo hash:net,port

              ipset add foo 192.168.0/24,25

              ipset add foo 10.1.0.0/16,80

              ipset test foo 192.168.0/24,25

   hash:ip,port,ip
       The  hash:ip,port,ip  set  type  uses  a  hash  to  store IP address, port number and a second IP address
       triples. The port number is interpreted together with a protocol (default TCP) and zero  protocol  number
       cannot be used.

       CREATE-OPTIONS := [ family { inet | inet6 } ] [ hashsizevalue ] [ maxelemvalue ] [ bucketsizevalue ] [
       timeoutvalue ] [ counters ] [ comment ] [ skbinfo ]

       ADD-ENTRY := ipaddr,[proto:]port,ipADD-OPTIONS := [ timeoutvalue ] [ packetsvalue ] [ bytesvalue ] [ commentstring ] [ skbmarkvalue ] [
       skbpriovalue ] [ skbqueuevalue ]

       DEL-ENTRY := ipaddr,[proto:]port,ipTEST-ENTRY := ipaddr,[proto:]port,ip

       For  the first ipaddr and [proto:]port parts of the elements see the descriptions at the hash:ip,port set
       type.

       The hash:ip,port,ip type of sets require three src/dst parameters of the set match and SET target  kernel
       modules.

       Examples:

              ipset create foo hash:ip,port,ip

              ipset add foo 192.168.1.1,80,10.0.0.1

              ipset test foo 192.168.1.1,udp:53,10.0.0.1

   hash:ip,port,net
       The  hash:ip,port,net  set  type  uses  a  hash  to  store IP address, port number and IP network address
       triples. The port number is interpreted together with a protocol (default TCP) and zero  protocol  number
       cannot be used. Network address with zero prefix size cannot be stored either.

       CREATE-OPTIONS := [ family { inet | inet6 } ] [ hashsizevalue ] [ maxelemvalue ] [ bucketsizevalue ] [
       timeoutvalue ] [ counters ] [ comment ] [ skbinfo ]

       ADD-ENTRY := ipaddr,[proto:]port,netaddrADD-OPTIONS  :=  [  timeoutvalue  ]  [ nomatch ] [ packetsvalue ] [ bytesvalue ] [ commentstring ] [
       skbmarkvalue ] [ skbpriovalue ] [ skbqueuevalue ]

       DEL-ENTRY := ipaddr,[proto:]port,netaddrTEST-ENTRY := ipaddr,[proto:]port,netaddr

       where netaddr := ip[/cidr]

       For the ipaddr and [proto:]port parts of the elements see the descriptions at the hash:ip,port set  type.
       For the netaddr part of the elements see the description at the hash:net set type.

       From  the  set netfilter match point of view the searching for a match always  starts  from  the smallest
       size  of netblock (most specific cidr) to the largest one (least specific cidr) added to the  set.   When
       adding/deleting  triples  to  the set by the SET netfilter target, it  will  be added/deleted by the most
       specific cidr which can be found in  the set, or by the host cidr value if the set is empty.

       The lookup time grows linearly with the number of the different cidr values added to the set.

       The hash:ip,port,net type of sets require three src/dst parameters of the set match and SET target kernel
       modules.

       Examples:

              ipset create foo hash:ip,port,net

              ipset add foo 192.168.1,80,10.0.0/24

              ipset add foo 192.168.2,25,10.1.0.0/16

              ipset test foo 192.168.1,80.10.0.0/24

   hash:ip,mark
       The hash:ip,mark set type uses a hash to store IP address and packet mark pairs.

       CREATE-OPTIONS := [ family { inet | inet6 } ] [ markmaskvalue ] [ hashsizevalue ] [ maxelemvalue  ]  [
       bucketsizevalue ] [ timeoutvalue ] [ counters ] [ comment ] [ skbinfo ]

       ADD-ENTRY := ipaddr,markADD-OPTIONS := [ timeoutvalue ] [ packetsvalue ] [ bytesvalue ] [ commentstring ] [ skbmarkvalue ] [
       skbpriovalue ] [ skbqueuevalue ]

       DEL-ENTRY := ipaddr,markTEST-ENTRY := ipaddr,mark

       Optional create options:

       markmaskvalue
              Allows  you to set bits you are interested in the packet mark. This values is then used to perform
              bitwise AND operation for every mark added.  markmask can be any value between 1  and  4294967295,
              by default all 32 bits are set.

       The mark can be any value between 0 and 4294967295.

       The  hash:ip,mark  type  of  sets  require  two src/dst parameters of the set match and SET target kernel
       modules.

       Examples:

              ipset create foo hash:ip,mark

              ipset add foo 192.168.1.0/24,555

              ipset add foo 192.168.1.1,0x63

              ipset add foo 192.168.1.1,111236

   hash:net,port,net
       The hash:net,port,net set type behaves similarly to hash:ip,port,net but accepts a cidr  value  for  both
       the first and last parameter. Either subnet is permitted to be a /0 should you wish to match port between
       all destinations.

       CREATE-OPTIONS := [ family { inet | inet6 } ] [ hashsizevalue ] [ maxelemvalue ] [ bucketsizevalue ] [
       timeoutvalue ] [ counters ] [ comment ] [ skbinfo ]

       ADD-ENTRY := netaddr,[proto:]port,netaddrADD-OPTIONS  :=  [  timeoutvalue  ]  [ nomatch ] [ packetsvalue ] [ bytesvalue ] [ commentstring ] [
       skbmarkvalue ] [ skbpriovalue ] [ skbqueuevalue ]

       DEL-ENTRY := netaddr,[proto:]port,netaddrTEST-ENTRY := netaddr,[proto:]port,netaddr

       where netaddr := ip[/cidr]

       For the [proto:]port part of the elements see the description at  the  hash:ip,port  set  type.  For  the
       netaddr part of the elements see the description at the hash:net set type.

       From  the  set netfilter match point of view the searching for a match always  starts  from  the smallest
       size  of netblock (most specific cidr) to the largest one (least specific cidr) added to the  set.   When
       adding/deleting  triples  to  the set by the SET netfilter target, it  will  be added/deleted by the most
       specific cidr which can be found in  the set, or by the host cidr value if the set is  empty.  The  first
       subnet has precedence when performing the most-specific lookup, just as for hash:net,net

       The  lookup  time grows linearly with the number of the different cidr values added to the set and by the
       number of secondary cidr values per primary.

       The hash:net,port,net type of sets require three src/dst parameters of  the  set  match  and  SET  target
       kernel modules.

       Examples:

              ipset create foo hash:net,port,net

              ipset add foo 192.168.1.0/24,0,10.0.0/24

              ipset add foo 192.168.2.0/24,25,10.1.0.0/16

              ipset test foo 192.168.1.1,80,10.0.0.1

   hash:net,iface
       The  hash:net,iface  set  type uses a hash to store different sized IP network address and interface name
       pairs.

       CREATE-OPTIONS := [ family { inet | inet6 } ] [ hashsizevalue ] [ maxelemvalue ] [ bucketsizevalue ] [
       timeoutvalue ] [ counters ] [ comment ] [ skbinfo ]

       ADD-ENTRY := netaddr,[physdev:]ifaceADD-OPTIONS := [ timeoutvalue ]  [ nomatch ] [ packetsvalue ] [ bytesvalue ]  [  commentstring  ]  [
       skbmarkvalue ] [ skbpriovalue ] [ skbqueuevalue ] [ wildcard ]

       DEL-ENTRY := netaddr,[physdev:]ifaceTEST-ENTRY := netaddr,[physdev:]iface

       where netaddr := ip[/cidr]

       For the netaddr part of the elements see the description at the hash:net set type.

       When adding/deleting/testing entries, if the cidr prefix parameter is not specified, then the host prefix
       value  is  assumed.  When  adding/deleting  entries,  the  exact element is added/deleted and overlapping
       elements are not checked by the kernel.  When testing entries, if a host  address  is  tested,  then  the
       kernel  tries  to  match  the  host  address  in  the  networks  added  to the set and reports the result
       accordingly.

       From the set netfilter match point of view the searching for a  match always  starts  from  the  smallest
       size   of  netblock  (most  specific prefix) to the largest one (least specific prefix) added to the set.
       When  adding/deleting IP addresses  to the set by the SET netfilter target, it  will  be added/deleted by
       the most specific prefix which can be found in  the set, or by the host prefix value if the set is empty.

       The  second  direction  parameter  of  the  set  match  and  SET  target  modules  corresponds   to   the
       incoming/outgoing  interface:  src to the incoming one (similar to the -i flag of iptables), while dst to
       the outgoing one (similar to the -o flag of iptables). When the interface is flagged with  physdev:,  the
       interface is interpreted as the incoming/outgoing bridge port.

       The lookup time grows linearly with the number of the different prefix values added to the set.

       The  internal restriction of the hash:net,iface set type is that the same network prefix cannot be stored
       with more than 64 different interfaces in a single set.

       Examples:

              ipset create foo hash:net,iface

              ipset add foo 192.168.0/24,eth0

              ipset add foo 10.1.0.0/16,eth1

              ipset test foo 192.168.0/24,eth0

   list:set
       The list:set type uses a simple list in which you can store set names.

       CREATE-OPTIONS := [ sizevalue ] [ timeoutvalue ] [ counters ] [ comment ] [ skbinfo ]

       ADD-ENTRY := setname [ { before | after } setname ]

       ADD-OPTIONS := [ timeoutvalue ] [ packetsvalue ] [ bytesvalue ] [ commentstring ] [ skbmarkvalue ] [
       skbpriovalue ] [ skbqueuevalue ]

       DEL-ENTRY := setname [ { before | after } setname ]

       TEST-ENTRY := setname [ { before | after } setname ]

       Optional create options:

       sizevalue
              The size of the list, the default is 8. The parameter is ignored since ipset version 6.24.

       By the ipset command you  can add, delete and test set names in a list:set type of set.

       By the set match or SET target of netfilter you can test, add or delete entries in the sets added to  the
       list:set  type of set. The match will try to find a matching entry in the sets and the target will try to
       add an entry to the first set to which it can be added.  The number of direction options of the match and
       target are important: sets which require more parameters than specified  are  skipped,  while  sets  with
       equal or less parameters are checked, elements added/deleted. For example if a and b are list:set type of
       sets then in the command

              iptables -m set --match-set a src,dst -j SET --add-set b src,dst

       the match and target will skip any set in a and b which stores data triples, but will match all sets with
       single  or double data storage in a set and stop matching at the first successful set, and add src to the
       first single or src,dst to the first double data storage set in b to which the entry can  be  added.  You
       can imagine a list:set type of set as an ordered union of the set elements.

       Please  note:  by  the ipset command you can add, delete and test the setnames in a list:set type of set,
       and not the presence of a set's member (such as an IP address).

ipset [ OPTIONS ] COMMAND [ COMMAND-OPTIONS ]

       COMMANDS  := { create | add | del | test | destroy | list | save | restore | flush | rename | swap | help
       | version | - }

       OPTIONS := { -exist | -output { plain | save | xml } | json } | -quiet | -resolve |  -sorted  |  -name  |
       -terse | -filefilename }

       ipsetcreateSETNAMETYPENAME [ CREATE-OPTIONS ]

       ipsetaddSETNAMEADD-ENTRY [ ADD-OPTIONS ]

       ipsetdelSETNAMEDEL-ENTRY [ DEL-OPTIONS ]

       ipsettestSETNAMETEST-ENTRY [ TEST-OPTIONS ]

       ipsetdestroy [ SETNAME ]

       ipsetlist [ SETNAME ]

       ipsetsave [ SETNAME ]

       ipsetrestoreipsetflush [ SETNAME ]

       ipsetrenameSETNAME-FROMSETNAME-TOipsetswapSETNAME-FROMSETNAME-TOipsethelp [ TYPENAME ]

       ipsetversionipset-