diff options
| -rw-r--r-- | docs/configuration/protocols/isis.rst | 263 |
1 files changed, 223 insertions, 40 deletions
diff --git a/docs/configuration/protocols/isis.rst b/docs/configuration/protocols/isis.rst index 416a42c3..ef9cc960 100644 --- a/docs/configuration/protocols/isis.rst +++ b/docs/configuration/protocols/isis.rst @@ -7,14 +7,18 @@ IS-IS ##### :abbr:`IS-IS (Intermediate System to Intermediate System)` is a link-state -interior gateway routing protocol which is described in ISO10589, -:rfc:`1195`, :rfc:`5308`. Like OSPF, IS-IS runs the Dijkstra shortest-path -first (SPF) algorithm to create a database of the network’s topology and, -from that database, to determine the best (that is, shortest) path to a -destination. The routers exchange topology information with their nearest -neighbors. IS-IS runs directly on the data link layer (Layer 2). IS-IS -addresses are called :abbr:`NETs (Network Entity Titles)` and can be -8 to 20 bytes long, but are generally 10 bytes long. +interior gateway protocol (IGP) which is described in ISO10589, +:rfc:`1195`, :rfc:`5308`. IS-IS runs the Dijkstra shortest-path first (SPF) +algorithm to create a database of the network’s topology, and +from that database to determine the best (that is, lowest cost) path to a +destination. The intermediate systems (the name for routers) exchange topology +information with their directly conencted neighbors. IS-IS runs directly on +the data link layer (Layer 2). IS-IS addresses are called +:abbr:`NETs (Network Entity Titles)` and can be 8 to 20 bytes long, but are +generally 10 bytes long. The tree database that is created with IS-IS is +similar to the one that is created with OSPF in that the paths chosen should +be similar. Comparisons to OSPF are inevitable and often are reasonable ones +to make in regards to the way a network will respond with either IGP. ******* General @@ -26,60 +30,76 @@ Configuration Mandatory Settings ------------------ +For IS-IS top operate correctly, one must do the equivalent of a Router ID in +CLNS. This Router ID is called the :abbr:`NET (Network Entity Title)`. This +must be unique for each and every router that is operating in IS-IS. It also +must not be duplicated otherwise the same issues that occur within OSPF will +occur within IS-IS when it comes to said duplication. + + .. cfgcmd:: set protocols isis net <network-entity-title> - This commad also sets network entity title (NET) provided in ISO format. + This commad sets network entity title (NET) provided in ISO format. - For example :abbr:`NET (Network Entity Title)` + Here is an example :abbr:`NET (Network Entity Title)` value: .. code-block:: none 49.0001.1921.6800.1002.00 - The IS-IS address consists of the following parts: + The CLNS address consists of the following parts: * :abbr:`AFI (Address family authority identifier)` - ``49`` The AFI value 49 is what IS-IS uses for private addressing. - * Area identifier: ``0001`` IS-IS area number (Area1) + * Area identifier: ``0001`` IS-IS area number (numberical area ``1``) * System identifier: ``1921.6800.1002`` - for system idetifiers we recommend - to use IP address or MAC address of the router itself. + to use IP address or MAC address of the router itself. The way to construct + this is to keep all of the zeroes of the router IP address, and then change + the periods from being every three numbers to every four numbers. The + address that is listed here is ``192.168.1.2``, which if expanded will turn + into ``192.168.001.002``. Then all one has to do is move the dots to have + four numbers instead of three. This gives us ``1921.6800.1002``. - * NET selector: ``00`` Must always be 00, to indicate "this system". + * :abbr:`NET (Network Entity Title)` selector: ``00`` Must always be 00. This + setting indicates "this system" or "local system." .. cfgcmd:: set protocols isis interface <interface> - This command activates ISIS adjacency on this interface. Note that the name - of ISIS instance must be the same as the one used to configure the ISIS - process. + This command enables IS-IS on this interface, and allows for + adjacency to occur. Note that the name of IS-IS instance must be + the same as the one used to configure the IS-IS process. + +IS-IS Global Configuration +-------------------------- .. cfgcmd:: set protocols isis dynamic-hostname - This command enables support for dynamic hostname. Dynamic hostname mapping - determined as described in :rfc:`2763`, Dynamic Hostname Exchange Mechanism - for IS-IS. + This command enables support for dynamic hostname TLV. Dynamic hostname + mapping determined as described in :rfc:`2763`, Dynamic Hostname + Exchange Mechanism for IS-IS. .. cfgcmd:: set protocols isis level <level-1|level-1-2|level-2> - This command defines the ISIS router behavior: + This command defines the IS-IS router behavior: - **level-1** Act as a station router only. - **level-1-2** Act as both a station router and an area router. - **level-2-only** Act as an area router only. + * **level-1** - Act as a station (Level 1) router only. + * **level-1-2** - Act as a station (Level 1) router and area (Level 2) router. + * **level-2-only** - Act as an area (Level 2) router only. .. cfgcmd:: set protocols isis lsp-mtu <size> - This command configures the maximum size of generated LSPs, in bytes. The - size range is 128 to 4352. + This command configures the maximum size of generated + :abbr:`LSPs (Link State PDUs)`, in bytes. The size range is 128 to 4352. .. cfgcmd:: set protocols isis metric-style <narrow|transition|wide> - This command sets old-style (ISO 10589) or new-style packet formats: + This command sets old-style (ISO 10589) or new style packet formats: - **narrow** Use old style of TLVs with narrow metric. - **transition** Send and accept both styles of TLVs during transition. - **wide** Use new style of TLVs to carry wider metric. + * **narrow** - Use old style of TLVs with narrow metric. + * **transition** - Send and accept both styles of TLVs during transition. + * **wide** - Use new style of TLVs to carry wider metric. .. cfgcmd:: set protocols isis purge-originator @@ -117,9 +137,9 @@ Interface Configuration This command specifies circuit type for interface: - * **level-1** Level-1 only adjacencies are formed. - * **level-1-2** Level-1-2 adjacencies are formed - * **level-2-only** Level-2 only adjacencies are formed + * **level-1** - Level-1 only adjacencies are formed. + * **level-1-2** - Level-1-2 adjacencies are formed + * **level-2-only** - Level-2 only adjacencies are formed .. cfgcmd:: set protocols isis interface <interface> hello-interval <seconds> @@ -261,12 +281,87 @@ Timers to IGP events. The process described in :rfc:`8405`. -******* -Example -******* +******** +Examples +******** + +Enable IS-IS +============ + +**Node 1:** + +.. code-block:: none + + set interfaces loopback lo address '192.168.255.255/32' + set interfaces ethernet eth1 address '192.0.2.1/24' + + set protocols isis interface eth1 + set protocols isis interface lo + set protocols isis net '49.0001.1921.6825.5255.00' + +**Node 2:** + +.. code-block:: none + + set interfaces ethernet eth1 address '192.0.2.2/24' + + set interfaces loopback lo address '192.168.255.254/32' + set interfaces ethernet eth1 address '192.0.2.2/24' + + set protocols isis interface eth1 + set protocols isis interface lo + set protocols isis net '49.0001.1921.6825.5254.00' + + + +This gives us the following neighborships, Level 1 and Level 2: + +.. code-block:: none + + Node-1@vyos:~$ show isis neighbor + Area VyOS: + System Id Interface L State Holdtime SNPA + vyos eth1 1 Up 28 0c87.6c09.0001 + vyos eth1 2 Up 28 0c87.6c09.0001 + + Node-2@vyos:~$ show isis neighbor + Area VyOS: + System Id Interface L State Holdtime SNPA + vyos eth1 1 Up 29 0c33.0280.0001 + vyos eth1 2 Up 28 0c33.0280.0001 + + + +Here's the IP routes that are populated. Just the loopback: + +.. code-block:: none + + Node-1@vyos:~$ show ip route isis + Codes: K - kernel route, C - connected, S - static, R - RIP, + O - OSPF, I - IS-IS, B - BGP, E - EIGRP, N - NHRP, + T - Table, v - VNC, V - VNC-Direct, A - Babel, F - PBR, + f - OpenFabric, + > - selected route, * - FIB route, q - queued, r - rejected, b - backup + t - trapped, o - offload failure + + I 192.0.2.0/24 [115/20] via 192.0.2.2, eth1 inactive, weight 1, 00:02:22 + I>* 192.168.255.254/32 [115/20] via 192.0.2.2, eth1, weight 1, 00:02:22 + + Node-2@vyos:~$ show ip route isis + Codes: K - kernel route, C - connected, S - static, R - RIP, + O - OSPF, I - IS-IS, B - BGP, E - EIGRP, N - NHRP, + T - Table, v - VNC, V - VNC-Direct, A - Babel, F - PBR, + f - OpenFabric, + > - selected route, * - FIB route, q - queued, r - rejected, b - backup + t - trapped, o - offload failure -Simple IS-IS configuration using 2 nodes and redistributing connected -interfaces. + I 192.0.2.0/24 [115/20] via 192.0.2.1, eth1 inactive, weight 1, 00:02:21 + I>* 192.168.255.255/32 [115/20] via 192.0.2.1, eth1, weight 1, 00:02:21 + + + +Enable IS-IS and redistribute routes not natively in IS-IS +========================================================== **Node 1:** @@ -293,11 +388,11 @@ interfaces. set protocols isis interface eth1 set protocols isis net '49.0001.1921.6800.2002.00' -Show ip routes on Node2: +Routes on Node 2: .. code-block:: none - vyos@r2:~$ show ip route isis + Node-2@r2:~$ show ip route isis Codes: K - kernel route, C - connected, S - static, R - RIP, O - OSPF, I - IS-IS, B - BGP, E - EIGRP, N - NHRP, T - Table, v - VNC, V - VNC-Direct, A - Babel, D - SHARP, @@ -305,3 +400,91 @@ Show ip routes on Node2: > - selected route, * - FIB route, q - queued route, r - rejected route I 203.0.113.0/24 [115/10] via 192.0.2.1, eth1, 00:03:42 + + + + +Enable IS-IS with Segment Routing (Experimental) +================================================ + +**Node 1:** + +.. code-block:: none + + set interfaces loopback lo address '192.168.255.255/32' + set interfaces ethernet eth1 address '192.0.2.1/24' + + set protocols isis interface eth1 + set protocols isis interface lo + set protocols isis net '49.0001.1921.6825.5255.00' + set protocols isis segment-routing global-block high-label-value '599' + set protocols isis segment-routing global-block low-label-value '550' + set protocols isis segment-routing prefix 192.168.255.255/32 index value '1' + set protocols isis segment-routing prefix 192.168.255.255/32 index explicit-null + set protocols mpls interface 'eth1' + +**Node 2:** + +.. code-block:: none + + set interfaces loopback lo address '192.168.255.254/32' + set interfaces ethernet eth1 address '192.0.2.2/24' + + set protocols isis interface eth1 + set protocols isis interface lo + set protocols isis net '49.0001.1921.6825.5254.00' + set protocols isis segment-routing global-block high-label-value '599' + set protocols isis segment-routing global-block low-label-value '550' + set protocols isis segment-routing prefix 192.168.255.254/32 index value '2' + set protocols isis segment-routing prefix 192.168.255.254/32 index explicit-null + set protocols mpls interface 'eth1' + + + +This gives us MPLS segment routing enabled and labels for far end loopbacks: + +.. code-block:: none + + Node-1@vyos:~$ show mpls table + Inbound Label Type Nexthop Outbound Label + ---------------------------------------------------------------------- + 552 SR (IS-IS) 192.0.2.2 IPv4 Explicit Null <-- Node-2 loopback learned on Node-1 + 15000 SR (IS-IS) 192.0.2.2 implicit-null + 15001 SR (IS-IS) fe80::e87:6cff:fe09:1 implicit-null + 15002 SR (IS-IS) 192.0.2.2 implicit-null + 15003 SR (IS-IS) fe80::e87:6cff:fe09:1 implicit-null + + Node-2@vyos:~$ show mpls table + Inbound Label Type Nexthop Outbound Label + --------------------------------------------------------------------- + 551 SR (IS-IS) 192.0.2.1 IPv4 Explicit Null <-- Node-1 loopback learned on Node-2 + 15000 SR (IS-IS) 192.0.2.1 implicit-null + 15001 SR (IS-IS) fe80::e33:2ff:fe80:1 implicit-null + 15002 SR (IS-IS) 192.0.2.1 implicit-null + 15003 SR (IS-IS) fe80::e33:2ff:fe80:1 implicit-null + +Here is the routing tables showing the MPLS segment routing label operations: + +.. code-block:: none + + Node-1@vyos:~$ show ip route isis + Codes: K - kernel route, C - connected, S - static, R - RIP, + O - OSPF, I - IS-IS, B - BGP, E - EIGRP, N - NHRP, + T - Table, v - VNC, V - VNC-Direct, A - Babel, F - PBR, + f - OpenFabric, + > - selected route, * - FIB route, q - queued, r - rejected, b - backup + t - trapped, o - offload failure + + I 192.0.2.0/24 [115/20] via 192.0.2.2, eth1 inactive, weight 1, 00:07:48 + I>* 192.168.255.254/32 [115/20] via 192.0.2.2, eth1, label IPv4 Explicit Null, weight 1, 00:03:39 + + Node-2@vyos:~$ show ip route isis + Codes: K - kernel route, C - connected, S - static, R - RIP, + O - OSPF, I - IS-IS, B - BGP, E - EIGRP, N - NHRP, + T - Table, v - VNC, V - VNC-Direct, A - Babel, F - PBR, + f - OpenFabric, + > - selected route, * - FIB route, q - queued, r - rejected, b - backup + t - trapped, o - offload failure + + I 192.0.2.0/24 [115/20] via 192.0.2.1, eth1 inactive, weight 1, 00:07:46 + I>* 192.168.255.255/32 [115/20] via 192.0.2.1, eth1, label IPv4 Explicit Null, weight 1, 00:03:43 |