diff options
Diffstat (limited to 'man/man8/ip-route.8.in')
| -rw-r--r-- | man/man8/ip-route.8.in | 1386 |
1 files changed, 1386 insertions, 0 deletions
diff --git a/man/man8/ip-route.8.in b/man/man8/ip-route.8.in new file mode 100644 index 0000000..194dc78 --- /dev/null +++ b/man/man8/ip-route.8.in @@ -0,0 +1,1386 @@ +.TH IP\-ROUTE 8 "13 Dec 2012" "iproute2" "Linux" +.SH "NAME" +ip-route \- routing table management +.SH "SYNOPSIS" +.sp +.ad l +.in +8 +.ti -8 +.B ip +.RI "[ " ip-OPTIONS " ]" +.B route +.RI " { " COMMAND " | " +.BR help " }" +.sp +.ti -8 + +.ti -8 +.BR "ip route" " { " +.BR show " | " flush " } " +.I SELECTOR + +.ti -8 +.BR "ip route save" +.I SELECTOR + +.ti -8 +.BR "ip route restore" + +.ti -8 +.B ip route get +.I ROUTE_GET_FLAGS +.IR ADDRESS " [ " +.BI from " ADDRESS " iif " STRING" +.RB " ] [ " oif +.IR STRING " ] [ " +.B mark +.IR MARK " ] [ " +.B tos +.IR TOS " ] [ " +.B vrf +.IR NAME " ] [ " +.B ipproto +.IR PROTOCOL " ] [ " +.B sport +.IR NUMBER " ] [ " +.B dport +.IR NUMBER " ] " + +.ti -8 +.BR "ip route" " { " add " | " del " | " change " | " append " | "\ +replace " } " +.I ROUTE + +.ti -8 +.IR SELECTOR " := " +.RB "[ " root +.IR PREFIX " ] [ " +.B match +.IR PREFIX " ] [ " +.B exact +.IR PREFIX " ] [ " +.B table +.IR TABLE_ID " ] [ " +.B vrf +.IR NAME " ] [ " +.B proto +.IR RTPROTO " ] [ " +.B type +.IR TYPE " ] [ " +.B scope +.IR SCOPE " ]" + +.ti -8 +.IR ROUTE " := " NODE_SPEC " [ " INFO_SPEC " ]" + +.ti -8 +.IR NODE_SPEC " := [ " TYPE " ] " PREFIX " [" +.B tos +.IR TOS " ] [ " +.B table +.IR TABLE_ID " ] [ " +.B proto +.IR RTPROTO " ] [ " +.B scope +.IR SCOPE " ] [ " +.B metric +.IR METRIC " ] [ " +.B ttl-propagate +.RB "{ " enabled " | " disabled " } ]" + +.ti -8 +.IR INFO_SPEC " := { " NH " | " +.B nhid +.IR ID " } " "OPTIONS FLAGS" " [" +.B nexthop +.IR NH " ] ..." + +.ti -8 +.IR NH " := [ " +.B encap +.IR ENCAP " ] [ " +.B via +[ +.IR FAMILY " ] " ADDRESS " ] [ " +.B dev +.IR STRING " ] [ " +.B weight +.IR NUMBER " ] " NHFLAGS + +.ti -8 +.IR FAMILY " := [ " +.BR inet " | " inet6 " | " mpls " | " bridge " | " link " ]" + +.ti -8 +.IR OPTIONS " := " FLAGS " [ " +.B mtu +.IR NUMBER " ] [ " +.B advmss +.IR NUMBER " ] [ " +.B as +[ +.B to +] +.IR ADDRESS " ]" +.B rtt +.IR TIME " ] [ " +.B rttvar +.IR TIME " ] [ " +.B reordering +.IR NUMBER " ] [ " +.B window +.IR NUMBER " ] [ " +.B cwnd +.IR NUMBER " ] [ " +.B ssthresh +.IR NUMBER " ] [ " +.B realms +.IR REALM " ] [ " +.B rto_min +.IR TIME " ] [ " +.B initcwnd +.IR NUMBER " ] [ " +.B initrwnd +.IR NUMBER " ] [ " +.B features +.IR FEATURES " ] [ " +.B quickack +.IR BOOL " ] [ " +.B congctl +.IR NAME " ] [ " +.B pref +.IR PREF " ] [ " +.B expires +.IR TIME " ] [" +.B fastopen_no_cookie +.IR BOOL " ]" + +.ti -8 +.IR TYPE " := [ " +.BR unicast " | " local " | " broadcast " | " multicast " | "\ +throw " | " unreachable " | " prohibit " | " blackhole " | " nat " ]" + +.ti -8 +.IR TABLE_ID " := [ " +.BR local "| " main " | " default " | " all " |" +.IR NUMBER " ]" + +.ti -8 +.IR SCOPE " := [ " +.BR host " | " link " | " global " |" +.IR NUMBER " ]" + +.ti -8 +.IR NHFLAGS " := [ " +.BR onlink " | " pervasive " ]" + +.ti -8 +.IR RTPROTO " := [ " +.BR kernel " | " boot " | " static " |" +.IR NUMBER " ]" + +.ti -8 +.IR FEATURES " := [ " +.BR ecn " | ]" + +.ti -8 +.IR PREF " := [ " +.BR low " | " medium " | " high " ]" + +.ti -8 +.IR ENCAP " := [ " +.IR ENCAP_MPLS " | " ENCAP_IP " | " ENCAP_BPF " | " +.IR ENCAP_SEG6 " | " ENCAP_SEG6LOCAL " | " ENCAP_IOAM6 " ] " + +.ti -8 +.IR ENCAP_MPLS " := " +.BR mpls " [ " +.IR LABEL " ] [" +.B ttl +.IR TTL " ]" + +.ti -8 +.IR ENCAP_IP " := " +.B ip +.B id +.IR TUNNEL_ID +.B dst +.IR REMOTE_IP " [ " +.B src +.IR SRC " ] [" +.B tos +.IR TOS " ] [" +.B ttl +.IR TTL " ]" + +.ti -8 +.IR ENCAP_BPF " := " +.BR bpf " [ " +.B in +.IR PROG " ] [" +.B out +.IR PROG " ] [" +.B xmit +.IR PROG " ] [" +.B headroom +.IR SIZE " ]" + +.ti -8 +.IR ENCAP_SEG6 " := " +.B seg6 +.BR mode " [ " +.BR encap " | " encap.red " | " inline " | " l2encap " | " l2encap.red " ] " +.B segs +.IR SEGMENTS " [ " +.B hmac +.IR KEYID " ]" + +.ti -8 +.IR ENCAP_SEG6LOCAL " := " +.B seg6local +.BR action +.IR SEG6_ACTION " [ " +.IR SEG6_ACTION_PARAM " ] [ " +.BR count " ] " + +.ti -8 +.IR ENCAP_IOAM6 " := " +.BR ioam6 " [" +.B freq +.IR K "/" N " ] " +.BR mode " [ " +.BR inline " | " encap " | " auto " ] [" +.B tundst +.IR ADDRESS " ] " +.B trace +.B prealloc +.B type +.IR IOAM6_TRACE_TYPE +.B ns +.IR IOAM6_NAMESPACE +.B size +.IR IOAM6_TRACE_SIZE + +.ti -8 +.IR ROUTE_GET_FLAGS " := " +.BR " [ " +.BR fibmatch +.BR " ] " + +.SH DESCRIPTION +.B ip route +is used to manipulate entries in the kernel routing tables. +.sp +.B Route types: + +.in +8 +.B unicast +- the route entry describes real paths to the destinations covered +by the route prefix. + +.sp +.B unreachable +- these destinations are unreachable. Packets are discarded and the +ICMP message +.I host unreachable +is generated. +The local senders get an +.I EHOSTUNREACH +error. + +.sp +.B blackhole +- these destinations are unreachable. Packets are discarded silently. +The local senders get an +.I EINVAL +error. + +.sp +.B prohibit +- these destinations are unreachable. Packets are discarded and the +ICMP message +.I communication administratively prohibited +is generated. The local senders get an +.I EACCES +error. + +.sp +.B local +- the destinations are assigned to this host. The packets are looped +back and delivered locally. + +.sp +.B broadcast +- the destinations are broadcast addresses. The packets are sent as +link broadcasts. + +.sp +.B throw +- a special control route used together with policy rules. If such a +route is selected, lookup in this table is terminated pretending that +no route was found. Without policy routing it is equivalent to the +absence of the route in the routing table. The packets are dropped +and the ICMP message +.I net unreachable +is generated. The local senders get an +.I ENETUNREACH +error. + +.sp +.B nat +- a special NAT route. Destinations covered by the prefix +are considered to be dummy (or external) addresses which require translation +to real (or internal) ones before forwarding. The addresses to translate to +are selected with the attribute +.BR "via" . +.B Warning: +Route NAT is no longer supported in Linux 2.6. + +.sp +.B anycast +.RI "- " "not implemented" +the destinations are +.I anycast +addresses assigned to this host. They are mainly equivalent +to +.B local +with one difference: such addresses are invalid when used +as the source address of any packet. + +.sp +.B multicast +- a special type used for multicast routing. It is not present in +normal routing tables. +.in -8 + +.P +.B Route tables: +Linux-2.x can pack routes into several routing tables identified +by a number in the range from 1 to 2^32-1 or by name from the file +.B @SYSCONFDIR@/rt_tables +By default all normal routes are inserted into the +.B main +table (ID 254) and the kernel only uses this table when calculating routes. +Values (0, 253, 254, and 255) are reserved for built-in use. + +.sp +Actually, one other table always exists, which is invisible but +even more important. It is the +.B local +table (ID 255). This table +consists of routes for local and broadcast addresses. The kernel maintains +this table automatically and the administrator usually need not modify it +or even look at it. + +The multiple routing tables enter the game when +.I policy routing +is used. + +.TP +ip route add +add new route +.TP +ip route change +change route +.TP +ip route replace +change or add new one +.RS +.TP +.BI to " TYPE PREFIX " (default) +the destination prefix of the route. If +.I TYPE +is omitted, +.B ip +assumes type +.BR "unicast" . +Other values of +.I TYPE +are listed above. +.I PREFIX +is an IP or IPv6 address optionally followed by a slash and the +prefix length. If the length of the prefix is missing, +.B ip +assumes a full-length host route. There is also a special +.I PREFIX +.B default +- which is equivalent to IP +.B 0/0 +or to IPv6 +.BR "::/0" . + +.TP +.BI tos " TOS" +.TP +.BI dsfield " TOS" +the Type Of Service (TOS) key. This key has no associated mask and +the longest match is understood as: First, compare the TOS +of the route and of the packet. If they are not equal, then the packet +may still match a route with a zero TOS. +.I TOS +is either an 8 bit hexadecimal number or an identifier +from +.BR "@SYSCONFDIR@/rt_dsfield" . + +.TP +.BI metric " NUMBER" +.TP +.BI preference " NUMBER" +the preference value of the route. +.I NUMBER +is an arbitrary 32bit number, where routes with lower values are preferred. + +.TP +.BI table " TABLEID" +the table to add this route to. +.I TABLEID +may be a number or a string from the file +.BR "@SYSCONFDIR@/rt_tables" . +If this parameter is omitted, +.B ip +assumes the +.B main +table, with the exception of +.BR local ", " broadcast " and " nat +routes, which are put into the +.B local +table by default. + +.TP +.BI vrf " NAME" +the vrf name to add this route to. Implicitly means the table +associated with the VRF. + +.TP +.BI dev " NAME" +the output device name. + +.TP +.BI via " [ FAMILY ] ADDRESS" +the address of the nexthop router, in the address family FAMILY. +Actually, the sense of this field depends on the route type. For +normal +.B unicast +routes it is either the true next hop router or, if it is a direct +route installed in BSD compatibility mode, it can be a local address +of the interface. For NAT routes it is the first address of the block +of translated IP destinations. + +.TP +.BI src " ADDRESS" +the source address to prefer when sending to the destinations +covered by the route prefix. + +.TP +.BI realm " REALMID" +the realm to which this route is assigned. +.I REALMID +may be a number or a string from the file +.BR "@SYSCONFDIR@/rt_realms" . + +.TP +.BI mtu " MTU" +.TP +.BI "mtu lock" " MTU" +the MTU along the path to the destination. If the modifier +.B lock +is not used, the MTU may be updated by the kernel due to +Path MTU Discovery. If the modifier +.B lock +is used, no path MTU discovery will be tried, all packets +will be sent without the DF bit in IPv4 case or fragmented +to MTU for IPv6. + +.TP +.BI window " NUMBER" +the maximal window for TCP to advertise to these destinations, +measured in bytes. It limits maximal data bursts that our TCP +peers are allowed to send to us. + +.TP +.BI rtt " TIME" +the initial RTT ('Round Trip Time') estimate. If no suffix is +specified the units are raw values passed directly to the +routing code to maintain compatibility with previous releases. +Otherwise if a suffix of s, sec or secs is used to specify +seconds and ms, msec or msecs to specify milliseconds. + + +.TP +.BI rttvar " TIME " "(Linux 2.3.15+ only)" +the initial RTT variance estimate. Values are specified as with +.BI rtt +above. + +.TP +.BI rto_min " TIME " "(Linux 2.6.23+ only)" +the minimum TCP Retransmission TimeOut to use when communicating with this +destination. Values are specified as with +.BI rtt +above. + +.TP +.BI ssthresh " NUMBER " "(Linux 2.3.15+ only)" +an estimate for the initial slow start threshold. + +.TP +.BI cwnd " NUMBER " "(Linux 2.3.15+ only)" +the clamp for congestion window. It is ignored if the +.B lock +flag is not used. + +.TP +.BI initcwnd " NUMBER " "(Linux 2.5.70+ only)" +the initial congestion window size for connections to this destination. +Actual window size is this value multiplied by the MSS +(``Maximal Segment Size'') for same connection. The default is +zero, meaning to use the values specified in RFC2414. + +.TP +.BI initrwnd " NUMBER " "(Linux 2.6.33+ only)" +the initial receive window size for connections to this destination. +Actual window size is this value multiplied by the MSS of the connection. +The default value is zero, meaning to use Slow Start value. + +.TP +.BI features " FEATURES " (Linux 3.18+ only) +Enable or disable per-route features. Only available feature at this +time is +.B ecn +to enable explicit congestion notification when initiating connections to the +given destination network. +When responding to a connection request from the given network, ecn will +also be used even if the +.B net.ipv4.tcp_ecn +sysctl is set to 0. + +.TP +.BI quickack " BOOL " "(Linux 3.11+ only)" +Enable or disable quick ack for connections to this destination. + +.TP +.BI fastopen_no_cookie " BOOL " "(Linux 4.15+ only)" +Enable TCP Fastopen without a cookie for connections to this destination. + +.TP +.BI congctl " NAME " "(Linux 3.20+ only)" +.TP +.BI "congctl lock" " NAME " "(Linux 3.20+ only)" +Sets a specific TCP congestion control algorithm only for a given destination. +If not specified, Linux keeps the current global default TCP congestion control +algorithm, or the one set from the application. If the modifier +.B lock +is not used, an application may nevertheless overwrite the suggested congestion +control algorithm for that destination. If the modifier +.B lock +is used, then an application is not allowed to overwrite the specified congestion +control algorithm for that destination, thus it will be enforced/guaranteed to +use the proposed algorithm. + +.TP +.BI advmss " NUMBER " "(Linux 2.3.15+ only)" +the MSS ('Maximal Segment Size') to advertise to these +destinations when establishing TCP connections. If it is not given, +Linux uses a default value calculated from the first hop device MTU. +(If the path to these destination is asymmetric, this guess may be wrong.) + +.TP +.BI reordering " NUMBER " "(Linux 2.3.15+ only)" +Maximal reordering on the path to this destination. +If it is not given, Linux uses the value selected with +.B sysctl +variable +.BR "net/ipv4/tcp_reordering" . + +.TP +.BI nexthop " NEXTHOP" +the nexthop of a multipath route. +.I NEXTHOP +is a complex value with its own syntax similar to the top level +argument lists: + +.in +8 +.BI via " [ FAMILY ] ADDRESS" +- is the nexthop router. +.sp + +.BI dev " NAME" +- is the output device. +.sp + +.BI weight " NUMBER" +- is a weight for this element of a multipath +route reflecting its relative bandwidth or quality. +.in -8 + +The internal buffer used in iproute2 limits the maximum number of nexthops that +may be specified in one go. If only +.I ADDRESS +is given, the current buffer size allows for 144 IPv6 nexthops and 253 IPv4 +ones. For IPv4, this effectively limits the number of nexthops possible per +route. With IPv6, further nexthops may be appended to the same route via +.B "ip route append" +command. + +.TP +.BI scope " SCOPE_VAL" +the scope of the destinations covered by the route prefix. +.I SCOPE_VAL +may be a number or a string from the file +.BR "@SYSCONFDIR@/rt_scopes" . +If this parameter is omitted, +.B ip +assumes scope +.B global +for all gatewayed +.B unicast +routes, scope +.B link +for direct +.BR unicast " and " broadcast +routes and scope +.BR host " for " local +routes. + +.TP +.BI protocol " RTPROTO" +the routing protocol identifier of this route. +.I RTPROTO +may be a number or a string from the file +.BR "@SYSCONFDIR@/rt_protos" . +If the routing protocol ID is not given, +.B ip assumes protocol +.B boot +(i.e. it assumes the route was added by someone who doesn't +understand what they are doing). Several protocol values have +a fixed interpretation. +Namely: + +.in +8 +.B redirect +- the route was installed due to an ICMP redirect. +.sp + +.B kernel +- the route was installed by the kernel during autoconfiguration. +.sp + +.B boot +- the route was installed during the bootup sequence. +If a routing daemon starts, it will purge all of them. +.sp + +.B static +- the route was installed by the administrator +to override dynamic routing. Routing daemon will respect them +and, probably, even advertise them to its peers. +.sp + +.B ra +- the route was installed by Router Discovery protocol. +.in -8 + +.sp +The rest of the values are not reserved and the administrator is free +to assign (or not to assign) protocol tags. + +.TP +.B onlink +pretend that the nexthop is directly attached to this link, +even if it does not match any interface prefix. + +.TP +.BI pref " PREF" +the IPv6 route preference. +.I PREF +is a string specifying the route preference as defined in RFC4191 for Router +Discovery messages. Namely: + +.in +8 +.B low +- the route has a lowest priority +.sp + +.B medium +- the route has a default priority +.sp + +.B high +- the route has a highest priority +.sp + +.TP +.BI nhid " ID" +use nexthop object with given id as nexthop specification. +.sp +.TP +.BI encap " ENCAPTYPE ENCAPHDR" +attach tunnel encapsulation attributes to this route. +.sp +.I ENCAPTYPE +is a string specifying the supported encapsulation type. Namely: + +.in +8 +.BI mpls +- encapsulation type MPLS +.sp +.BI ip +- IP encapsulation (Geneve, GRE, VXLAN, ...) +.sp +.BI bpf +- Execution of BPF program +.sp +.BI seg6 +- encapsulation type IPv6 Segment Routing +.sp +.BI seg6local +- local SRv6 segment processing +.sp +.BI ioam6 +- encapsulation type IPv6 IOAM +.sp +.BI xfrm +- encapsulation type XFRM + +.in -8 +.I ENCAPHDR +is a set of encapsulation attributes specific to the +.I ENCAPTYPE. + +.in +8 +.B mpls +.in +2 +.I MPLSLABEL +- mpls label stack with labels separated by +.I "/" +.sp + +.B ttl +.I TTL +- TTL to use for MPLS header or 0 to inherit from IP header +.in -2 +.sp + +.B ip +.in +2 +.B id +.I TUNNEL_ID +.B dst +.IR REMOTE_IP " [ " +.B src +.IR SRC " ] [" +.B tos +.IR TOS " ] [" +.B ttl +.IR TTL " ] [ " +.BR key " ] [ " csum " ] [ " seq " ] " +.in -2 +.sp + +.B bpf +.in +2 +.B in +.I PROG +- BPF program to execute for incoming packets +.sp + +.B out +.I PROG +- BPF program to execute for outgoing packets +.sp + +.B xmit +.I PROG +- BPF program to execute for transmitted packets +.sp + +.B headroom +.I SIZE +- Size of header BPF program will attach (xmit) +.in -2 +.sp + +.B seg6 +.in +2 +.B mode inline +- Directly insert Segment Routing Header after IPv6 header +.sp + +.B mode encap +- Encapsulate packet in an outer IPv6 header with SRH +.sp + +.B mode encap.red +- Encapsulate packet in an outer IPv6 header with SRH applying the +reduced segment list. When there is only one segment and the HMAC is +not present, the SRH is omitted. +.sp + +.B mode l2encap +- Encapsulate ingress L2 frame within an outer IPv6 header and SRH +.sp + +.B mode l2encap.red +- Encapsulate ingress L2 frame within an outer IPv6 header and SRH +applying the reduced segment list. When there is only one segment +and the HMAC is not present, the SRH is omitted. +.sp + +.I SEGMENTS +- List of comma-separated IPv6 addresses +.sp + +.I KEYID +- Numerical value in decimal representation. See \fBip-sr\fR(8). +.in -2 +.sp + +.B seg6local +.in +2 +.IR SEG6_ACTION " [ " +.IR SEG6_ACTION_PARAM " ] [ " +.BR count " ] " +- Operation to perform on matching packets. The optional \fBcount\fR +attribute is used to collect statistics on the processing of actions. +Three counters are implemented: 1) packets correctly processed; +2) bytes correctly processed; 3) packets that cause a processing error +(i.e., missing SID List, wrong SID List, etc). To retrieve the counters +related to an action use the \fB-s\fR flag in the \fBshow\fR command. +The following actions are currently supported (\fBLinux 4.14+ only\fR). +.in +2 + +.BR End " [ " flavors +.IR FLAVORS " ] " +- Regular SRv6 processing as intermediate segment endpoint. +This action only accepts packets with a non-zero Segments Left +value. Other matching packets are dropped. The presence of flavors +can change the regular processing of an End behavior according to +the user-provided Flavor operations and information carried in the packet. +See \fBFlavors parameters\fR section. + +.B End.X nh6 +.I NEXTHOP +- Regular SRv6 processing as intermediate segment endpoint. +Additionally, forward processed packets to given next-hop. +This action only accepts packets with a non-zero Segments Left +value. Other matching packets are dropped. + +.B End.DX6 nh6 +.I NEXTHOP +- Decapsulate inner IPv6 packet and forward it to the +specified next-hop. If the argument is set to ::, then +the next-hop is selected according to the local selection +rules. This action only accepts packets with either a zero Segments +Left value or no SRH at all, and an inner IPv6 packet. Other +matching packets are dropped. + +.BR End.DT6 " { " table " | " vrftable " } " +.I TABLEID +- Decapsulate the inner IPv6 packet and forward it according to the +specified lookup table. +.I TABLEID +is either a number or a string from the file +.BR "@SYSCONFDIR@/rt_tables" . +If +.B vrftable +is used, the argument must be a VRF device associated with +the table id. Moreover, the VRF table associated with the +table id must be configured with the VRF strict mode turned +on (net.vrf.strict_mode=1). This action only accepts packets +with either a zero Segments Left value or no SRH at all, +and an inner IPv6 packet. Other matching packets are dropped. + +.B End.DT4 vrftable +.I TABLEID +- Decapsulate the inner IPv4 packet and forward it according to the +specified lookup table. +.I TABLEID +is either a number or a string from the file +.BR "@SYSCONFDIR@/rt_tables" . +The argument must be a VRF device associated with the table id. +Moreover, the VRF table associated with the table id must be configured +with the VRF strict mode turned on (net.vrf.strict_mode=1). This action +only accepts packets with either a zero Segments Left value or no SRH +at all, and an inner IPv4 packet. Other matching packets are dropped. + +.B End.DT46 vrftable +.I TABLEID +- Decapsulate the inner IPv4 or IPv6 packet and forward it according +to the specified lookup table. +.I TABLEID +is either a number or a string from the file +.BR "@SYSCONFDIR@/rt_tables" . +The argument must be a VRF device associated with the table id. +Moreover, the VRF table associated with the table id must be configured +with the VRF strict mode turned on (net.vrf.strict_mode=1). This action +only accepts packets with either a zero Segments Left value or no SRH +at all, and an inner IPv4 or IPv6 packet. Other matching packets are +dropped. + +.B End.B6 srh segs +.IR SEGMENTS " [ " +.B hmac +.IR KEYID " ] " +- Insert the specified SRH immediately after the IPv6 header, +update the DA with the first segment of the newly inserted SRH, +then forward the resulting packet. The original SRH is not +modified. This action only accepts packets with a non-zero +Segments Left value. Other matching packets are dropped. + +.B End.B6.Encaps srh segs +.IR SEGMENTS " [ " +.B hmac +.IR KEYID " ] " +- Regular SRv6 processing as intermediate segment endpoint. +Additionally, encapsulate the matching packet within an outer IPv6 header +followed by the specified SRH. The destination address of the outer IPv6 +header is set to the first segment of the new SRH. The source +address is set as described in \fBip-sr\fR(8). + +.B Flavors parameters + +The flavors represent additional operations that can modify or extend a +subset of the existing behaviors. +.in +2 + +.B flavors +.IR OPERATION "[," OPERATION "] [" ATTRIBUTES "]" +.in +2 + +.IR OPERATION " := { " +.BR psp " | " +.BR usp " | " +.BR usd " | " +.BR next-csid " }" + +.IR ATTRIBUTES " := {" +.IR "KEY VALUE" " } [" +.IR ATTRIBUTES " ]" + +.IR KEY " := { " +.BR lblen " | " +.BR nflen " } " +.in -2 + +.B psp +- Penultimate Segment Pop of the SRH (not yet supported in kernel) + +.B usp +- Ultimate Segment Pop of the SRH (not yet supported in kernel) + +.B usd +- Ultimate Segment Decapsulation (not yet supported in kernel) + +.B next-csid +- The NEXT-C-SID mechanism offers the possibility of encoding +several SRv6 segments within a single 128 bit SID address. The NEXT-C-SID +flavor can be configured to support user-provided Locator-Block and +Locator-Node Function lengths. If Locator-Block and/or Locator-Node Function +lengths are not provided by the user during configuration of an SRv6 End +behavior instance with NEXT-C-SID flavor, the default value is 32-bit for +Locator-Block and 16-bit for Locator-Node Function. + +.BI lblen " VALUE " +- defines the Locator-Block length for NEXT-C-SID flavor. +The Locator-Block length must be greater than 0 and evenly divisible by 8. This +attribute can be used only with NEXT-C-SID flavor. + +.BI nflen " VALUE " +- defines the Locator-Node Function length for NEXT-C-SID +flavors. The Locator-Node Function length must be greater than 0 and evenly +divisible by 8. This attribute can be used only with NEXT-C-SID flavor. +.in -4 + +.B ioam6 +.in +2 +.B freq K/N +- Inject IOAM in K packets every N packets (default is 1/1). + +.B mode inline +- Directly insert IOAM after IPv6 header (default mode). +.sp + +.B mode encap +- Encapsulate packet in an outer IPv6 header with IOAM. +.sp + +.B mode auto +- Automatically use inline mode for local packets and encap mode for in-transit +packets. +.sp + +.B tundst +.I ADDRESS +- IPv6 address of the tunnel destination (outer header), not used with inline +mode. + +.B type +.I IOAM6_TRACE_TYPE +- List of IOAM data required in the trace, represented by a bitfield (24 bits). +.sp + +.B ns +.I IOAM6_NAMESPACE +- Numerical value to represent an IOAM namespace. See \fBip-ioam\fR(8). +.sp + +.B size +.I IOAM6_TRACE_SIZE +- Size, in octets, of the pre-allocated trace data block. +.in -2 + +.B xfrm +.in +2 +.B if_id +.I IF_ID +.B " [ link_dev +.IR LINK_DEV " ] " +.in -4 + +.in -8 + +.TP +.BI expires " TIME " "(Linux 4.4+ only)" +the route will be deleted after the expires time. +.B Only +support IPv6 at present. + +.TP +.BR ttl-propagate " { " enabled " | " disabled " } " +Control whether TTL should be propagated from any encap into the +un-encapsulated packet, overriding any global configuration. Only +supported for MPLS at present. +.RE + +.TP +ip route delete +delete route +.RS +.B ip route del +has the same arguments as +.BR "ip route add" , +but their semantics are a bit different. + +Key values +.RB "(" to ", " tos ", " preference " and " table ")" +select the route to delete. If optional attributes are present, +.B ip +verifies that they coincide with the attributes of the route to delete. +If no route with the given key and attributes was found, +.B ip route del +fails. +.RE + +.TP +ip route show +list routes +.RS +the command displays the contents of the routing tables or the route(s) +selected by some criteria. + +.TP +.BI to " SELECTOR " (default) +only select routes from the given range of destinations. +.I SELECTOR +consists of an optional modifier +.RB "(" root ", " match " or " exact ")" +and a prefix. +.BI root " PREFIX" +selects routes with prefixes not shorter than +.IR PREFIX "." +F.e. +.BI root " 0/0" +selects the entire routing table. +.BI match " PREFIX" +selects routes with prefixes not longer than +.IR PREFIX "." +F.e. +.BI match " 10.0/16" +selects +.IR 10.0/16 "," +.IR 10/8 " and " 0/0 , +but it does not select +.IR 10.1/16 " and " 10.0.0/24 . +And +.BI exact " PREFIX" +(or just +.IR PREFIX ")" +selects routes with this exact prefix. If neither of these options +are present, +.B ip +assumes +.BI root " 0/0" +i.e. it lists the entire table. + +.TP +.BI tos " TOS" +.TP +.BI dsfield " TOS" +only select routes with the given TOS. + +.TP +.BI table " TABLEID" +show the routes from this table(s). The default setting is to show table +.BR main "." +.I TABLEID +may either be the ID of a real table or one of the special values: +.sp +.in +8 +.B all +- list all of the tables. +.sp +.B cache +- dump the routing cache. +.in -8 + +.TP +.BI vrf " NAME" +show the routes for the table associated with the vrf name + +.TP +.B cloned +.TP +.B cached +list cloned routes i.e. routes which were dynamically forked from +other routes because some route attribute (f.e. MTU) was updated. +Actually, it is equivalent to +.BR "table cache" "." + +.TP +.BI from " SELECTOR" +the same syntax as for +.BR to "," +but it binds the source address range rather than destinations. +Note that the +.B from +option only works with cloned routes. + +.TP +.BI protocol " RTPROTO" +only list routes of this protocol. + +.TP +.BI scope " SCOPE_VAL" +only list routes with this scope. + +.TP +.BI type " TYPE" +only list routes of this type. + +.TP +.BI dev " NAME" +only list routes going via this device. + +.TP +.BI via " [ FAMILY ] PREFIX" +only list routes going via the nexthop routers selected by +.IR PREFIX "." + +.TP +.BI src " PREFIX" +only list routes with preferred source addresses selected +by +.IR PREFIX "." + +.TP +.BI realm " REALMID" +.TP +.BI realms " FROMREALM/TOREALM" +only list routes with these realms. +.RE + +.TP +ip route flush +flush routing tables +.RS +this command flushes routes selected by some criteria. + +.sp +The arguments have the same syntax and semantics as the arguments of +.BR "ip route show" , +but routing tables are not listed but purged. The only difference is +the default action: +.B show +dumps all the IP main routing table but +.B flush +prints the helper page. + +.sp +With the +.B -statistics +option, the command becomes verbose. It prints out the number of +deleted routes and the number of rounds made to flush the routing +table. If the option is given +twice, +.B ip route flush +also dumps all the deleted routes in the format described in the +previous subsection. +.RE + +.TP +ip route get +get a single route +.RS +this command gets a single route to a destination and prints its +contents exactly as the kernel sees it. + +.TP +.BI fibmatch +Return full fib lookup matched route. Default is to return the resolved +dst entry + +.TP +.BI to " ADDRESS " (default) +the destination address. + +.TP +.BI from " ADDRESS" +the source address. + +.TP +.BI tos " TOS" +.TP +.BI dsfield " TOS" +the Type Of Service. + +.TP +.BI iif " NAME" +the device from which this packet is expected to arrive. + +.TP +.BI oif " NAME" +force the output device on which this packet will be routed. + +.TP +.BI mark " MARK" +the firewall mark +.RB ( "fwmark" ) + +.TP +.BI vrf " NAME" +force the vrf device on which this packet will be routed. + +.TP +.BI ipproto " PROTOCOL" +ip protocol as seen by the route lookup + +.TP +.BI sport " NUMBER" +source port as seen by the route lookup + +.TP +.BI dport " NUMBER" +destination port as seen by the route lookup + +.TP +.B connected +if no source address +.RB "(option " from ")" +was given, relookup the route with the source set to the preferred +address received from the first lookup. +If policy routing is used, it may be a different route. + +.P +Note that this operation is not equivalent to +.BR "ip route show" . +.B show +shows existing routes. +.B get +resolves them and creates new clones if necessary. Essentially, +.B get +is equivalent to sending a packet along this path. +If the +.B iif +argument is not given, the kernel creates a route +to output packets towards the requested destination. +This is equivalent to pinging the destination +with a subsequent +.BR "ip route ls cache" , +however, no packets are actually sent. With the +.B iif +argument, the kernel pretends that a packet arrived from this interface +and searches for a path to forward the packet. +.RE + +.TP +ip route save +save routing table information to stdout +.RS +This command behaves like +.BR "ip route show" +except that the output is raw data suitable for passing to +.BR "ip route restore" . +.RE + +.TP +ip route restore +restore routing table information from stdin +.RS +This command expects to read a data stream as returned from +.BR "ip route save" . +It will attempt to restore the routing table information exactly as +it was at the time of the save, so any translation of information +in the stream (such as device indexes) must be done first. Any existing +routes are left unchanged. Any routes specified in the data stream that +already exist in the table will be ignored. +.RE + +.SH NOTES +Starting with Linux kernel version 3.6, there is no routing cache for IPv4 +anymore. Hence +.B "ip route show cached" +will never print any entries on systems with this or newer kernel versions. + +.SH EXAMPLES +.PP +ip ro +.RS 4 +Show all route entries in the kernel. +.RE +.PP +ip route add default via 192.168.1.1 dev eth0 +.RS 4 +Adds a default route (for all addresses) via the local gateway 192.168.1.1 that can +be reached on device eth0. +.RE +.PP +ip route add 10.1.1.0/30 encap mpls 200/300 via 10.1.1.1 dev eth0 +.RS 4 +Adds an ipv4 route with mpls encapsulation attributes attached to it. +.RE +.PP +ip -6 route add 2001:db8:1::/64 encap seg6 mode encap segs 2001:db8:42::1,2001:db8:ffff::2 dev eth0 +.RS 4 +Adds an IPv6 route with SRv6 encapsulation and two segments attached. +.RE +.PP +ip -6 route add 2001:db8:1::/64 encap seg6local action End.DT46 vrftable 100 dev vrf100 +.RS 4 +Adds an IPv6 route with SRv6 decapsulation and forward with lookup in VRF table. +.RE +.PP +ip -6 route add 2001:db8:1::/64 encap seg6local action End flavors next-csid dev eth0 +.RS 4 +Adds an IPv6 route with SRv6 End behavior with next-csid flavor enabled. +.RE +.PP +ip -6 route add 2001:db8:1::/64 encap seg6local action End flavors next-csid lblen 48 nflen 16 dev eth0 +.RS 4 +Adds an IPv6 route with SRv6 End behavior with next-csid flavor enabled and user-provided Locator-Block and Locator-Node Function lengths. +.RE +.PP +ip -6 route add 2001:db8:1::/64 encap ioam6 freq 2/5 mode encap tundst 2001:db8:42::1 trace prealloc type 0x800000 ns 1 size 12 dev eth0 +.RS 4 +Adds an IPv6 route with an IOAM Pre-allocated Trace encapsulation (ip6ip6) that only includes the hop limit and the node id, configured for the IOAM namespace 1 and a pre-allocated data block of 12 octets (will be injected in 2 packets every 5 packets). +.RE +.PP +ip route add 10.1.1.0/30 nhid 10 +.RS 4 +Adds an ipv4 route using nexthop object with id 10. +.RE +.SH SEE ALSO +.br +.BR ip (8) + +.SH AUTHOR +Original Manpage by Michail Litvak <mci@owl.openwall.com> |