1: @node Zebra
2: @chapter Zebra
3:
4: @c SYNOPSIS
5: @command{zebra} is an IP routing manager. It provides kernel routing
6: table updates, interface lookups, and redistribution of routes between
7: different routing protocols.
8:
9: @menu
10: * Invoking zebra:: Running the program
11: * Interface Commands:: Commands for zebra interfaces
12: * Static Route Commands:: Commands for adding static routes
13: * zebra Route Filtering:: Commands for zebra route filtering
14: * zebra FIB push interface:: Interface to optional FPM component
15: * zebra Terminal Mode Commands:: Commands for zebra's VTY
16: @end menu
17:
18:
19: @node Invoking zebra
20: @section Invoking zebra
21:
22: Besides the common invocation options (@pxref{Common Invocation Options}), the
23: @command{zebra} specific invocation options are listed below.
24:
25: @table @samp
26: @item -b
27: @itemx --batch
28: Runs in batch mode. @command{zebra} parses configuration file and terminates
29: immediately.
30:
31: @item -k
32: @itemx --keep_kernel
33: When zebra starts up, don't delete old self inserted routes.
34:
35: @item -r
36: @itemx --retain
37: When program terminates, retain routes added by zebra.
38:
39: @end table
40:
41: @node Interface Commands
42: @section Interface Commands
43:
44: @deffn Command {interface @var{ifname}} {}
45: @end deffn
46:
47: @deffn {Interface Command} {shutdown} {}
48: @deffnx {Interface Command} {no shutdown} {}
49: Up or down the current interface.
50: @end deffn
51:
52: @deffn {Interface Command} {ip address @var{address/prefix}} {}
53: @deffnx {Interface Command} {ipv6 address @var{address/prefix}} {}
54: @deffnx {Interface Command} {no ip address @var{address/prefix}} {}
55: @deffnx {Interface Command} {no ipv6 address @var{address/prefix}} {}
56: Set the IPv4 or IPv6 address/prefix for the interface.
57: @end deffn
58:
59: @deffn {Interface Command} {ip address @var{address/prefix} secondary} {}
60: @deffnx {Interface Command} {no ip address @var{address/prefix} secondary} {}
61: Set the secondary flag for this address. This causes ospfd to not treat the
62: address as a distinct subnet.
63: @end deffn
64:
65: @deffn {Interface Command} {description @var{description} ...} {}
66: Set description for the interface.
67: @end deffn
68:
69: @deffn {Interface Command} {multicast} {}
70: @deffnx {Interface Command} {no multicast} {}
71: Enable or disables multicast flag for the interface.
72: @end deffn
73:
74: @deffn {Interface Command} {bandwidth <1-10000000>} {}
75: @deffnx {Interface Command} {no bandwidth <1-10000000>} {}
76: Set bandwidth value of the interface in kilobits/sec. This is for
77: calculating OSPF cost. This command does not affect the actual device
78: configuration.
79: @end deffn
80:
81: @deffn {Interface Command} {link-detect} {}
82: @deffnx {Interface Command} {no link-detect} {}
83: Enable/disable link-detect on platforms which support this. Currently
84: only Linux and Solaris, and only where network interface drivers support reporting
85: link-state via the IFF_RUNNING flag.
86: @end deffn
87:
88: @node Static Route Commands
89: @section Static Route Commands
90:
91: Static routing is a very fundamental feature of routing technology. It
92: defines static prefix and gateway.
93:
94: @deffn Command {ip route @var{network} @var{gateway}} {}
95: @var{network} is destination prefix with format of A.B.C.D/M.
96: @var{gateway} is gateway for the prefix. When @var{gateway} is
97: A.B.C.D format. It is taken as a IPv4 address gateway. Otherwise it
98: is treated as an interface name. If the interface name is @var{null0} then
99: zebra installs a blackhole route.
100:
101: @example
102: ip route 10.0.0.0/8 10.0.0.2
103: ip route 10.0.0.0/8 ppp0
104: ip route 10.0.0.0/8 null0
105: @end example
106:
107: First example defines 10.0.0.0/8 static route with gateway 10.0.0.2.
108: Second one defines the same prefix but with gateway to interface ppp0. The
109: third install a blackhole route.
110: @end deffn
111:
112: @deffn Command {ip route @var{network} @var{netmask} @var{gateway}} {}
113: This is alternate version of above command. When @var{network} is
114: A.B.C.D format, user must define @var{netmask} value with A.B.C.D
115: format. @var{gateway} is same option as above command
116:
117: @example
118: ip route 10.0.0.0 255.255.255.0 10.0.0.2
119: ip route 10.0.0.0 255.255.255.0 ppp0
120: ip route 10.0.0.0 255.255.255.0 null0
121: @end example
122:
123: These statements are equivalent to those in the previous example.
124: @end deffn
125:
126: @deffn Command {ip route @var{network} @var{gateway} @var{distance}} {}
127: Installs the route with the specified distance.
128: @end deffn
129:
130: Multiple nexthop static route
131:
132: @example
133: ip route 10.0.0.1/32 10.0.0.2
134: ip route 10.0.0.1/32 10.0.0.3
135: ip route 10.0.0.1/32 eth0
136: @end example
137:
138: If there is no route to 10.0.0.2 and 10.0.0.3, and interface eth0
139: is reachable, then the last route is installed into the kernel.
140:
141: If zebra has been compiled with multipath support, and both 10.0.0.2 and
142: 10.0.0.3 are reachable, zebra will install a multipath route via both
143: nexthops, if the platform supports this.
144:
145: @example
146: zebra> show ip route
147: S> 10.0.0.1/32 [1/0] via 10.0.0.2 inactive
148: via 10.0.0.3 inactive
149: * is directly connected, eth0
150: @end example
151:
152: @example
153: ip route 10.0.0.0/8 10.0.0.2
154: ip route 10.0.0.0/8 10.0.0.3
155: ip route 10.0.0.0/8 null0 255
156: @end example
157:
158: This will install a multihop route via the specified next-hops if they are
159: reachable, as well as a high-metric blackhole route, which can be useful to
160: prevent traffic destined for a prefix to match less-specific routes (eg
161: default) should the specified gateways not be reachable. Eg:
162:
163: @example
164: zebra> show ip route 10.0.0.0/8
165: Routing entry for 10.0.0.0/8
166: Known via "static", distance 1, metric 0
167: 10.0.0.2 inactive
168: 10.0.0.3 inactive
169:
170: Routing entry for 10.0.0.0/8
171: Known via "static", distance 255, metric 0
172: directly connected, Null0
173: @end example
174:
175: @deffn Command {ipv6 route @var{network} @var{gateway}} {}
176: @deffnx Command {ipv6 route @var{network} @var{gateway} @var{distance}} {}
177: These behave similarly to their ipv4 counterparts.
178: @end deffn
179:
180:
181: @deffn Command {table @var{tableno}} {}
182: Select the primary kernel routing table to be used. This only works
183: for kernels supporting multiple routing tables (like GNU/Linux 2.2.x
184: and later). After setting @var{tableno} with this command,
185: static routes defined after this are added to the specified table.
186: @end deffn
187:
188: @node zebra Route Filtering
189: @section zebra Route Filtering
190: Zebra supports @command{prefix-list} and @command{route-map} to match
191: routes received from other quagga components. The
192: @command{permit}/@command{deny} facilities provided by these commands
193: can be used to filter which routes zebra will install in the kernel.
194:
195: @deffn Command {ip protocol @var{protocol} route-map @var{routemap}} {}
196: Apply a route-map filter to routes for the specified protocol. @var{protocol}
197: can be @b{any} or one of
198: @b{system},
199: @b{kernel},
200: @b{connected},
201: @b{static},
202: @b{rip},
203: @b{ripng},
204: @b{ospf},
205: @b{ospf6},
206: @b{isis},
207: @b{bgp},
208: @b{hsls}.
209: @end deffn
210:
211: @deffn {Route Map} {set src @var{address}}
212: Within a route-map, set the preferred source address for matching routes
213: when installing in the kernel.
214: @end deffn
215:
216: @example
217: The following creates a prefix-list that matches all addresses, a route-map
218: that sets the preferred source address, and applies the route-map to all
219: @command{rip} routes.
220:
221: @group
222: ip prefix-list ANY permit 0.0.0.0/0 le 32
223: route-map RM1 permit 10
224: match ip address prefix-list ANY
225: set src 10.0.0.1
226:
227: ip protocol rip route-map RM1
228: @end group
229: @end example
230:
231: @node zebra FIB push interface
232: @section zebra FIB push interface
233:
234: Zebra supports a 'FIB push' interface that allows an external
235: component to learn the forwarding information computed by the Quagga
236: routing suite.
237:
238: In Quagga, the Routing Information Base (RIB) resides inside
239: zebra. Routing protocols communicate their best routes to zebra, and
240: zebra computes the best route across protocols for each prefix. This
241: latter information makes up the Forwarding Information Base
242: (FIB). Zebra feeds the FIB to the kernel, which allows the IP stack in
243: the kernel to forward packets according to the routes computed by
244: Quagga. The kernel FIB is updated in an OS-specific way. For example,
245: the @code{netlink} interface is used on Linux, and route sockets are
246: used on FreeBSD.
247:
248: The FIB push interface aims to provide a cross-platform mechanism to
249: support scenarios where the router has a forwarding path that is
250: distinct from the kernel, commonly a hardware-based fast path. In
251: these cases, the FIB needs to be maintained reliably in the fast path
252: as well. We refer to the component that programs the forwarding plane
253: (directly or indirectly) as the Forwarding Plane Manager or FPM.
254:
255: The FIB push interface comprises of a TCP connection between zebra and
256: the FPM. The connection is initiated by zebra -- that is, the FPM acts
257: as the TCP server.
258:
259: The relevant zebra code kicks in when zebra is configured with the
260: @code{--enable-fpm} flag. Zebra periodically attempts to connect to
261: the well-known FPM port. Once the connection is up, zebra starts
262: sending messages containing routes over the socket to the FPM. Zebra
263: sends a complete copy of the forwarding table to the FPM, including
264: routes that it may have picked up from the kernel. The existing
265: interaction of zebra with the kernel remains unchanged -- that is, the
266: kernel continues to receive FIB updates as before.
267:
268: The format of the messages exchanged with the FPM is defined by the
269: file @file{fpm/fpm.h} in the quagga tree.
270:
271: The zebra FPM interface uses replace semantics. That is, if a 'route
272: add' message for a prefix is followed by another 'route add' message,
273: the information in the second message is complete by itself, and
274: replaces the information sent in the first message.
275:
276: If the connection to the FPM goes down for some reason, zebra sends
277: the FPM a complete copy of the forwarding table(s) when it reconnects.
278:
279: @node zebra Terminal Mode Commands
280: @section zebra Terminal Mode Commands
281:
282: @deffn Command {show ip route} {}
283: Display current routes which zebra holds in its database.
284:
285: @example
286: @group
287: Router# show ip route
288: Codes: K - kernel route, C - connected, S - static, R - RIP,
289: B - BGP * - FIB route.
290:
291: K* 0.0.0.0/0 203.181.89.241
292: S 0.0.0.0/0 203.181.89.1
293: C* 127.0.0.0/8 lo
294: C* 203.181.89.240/28 eth0
295: @end group
296: @end example
297: @end deffn
298:
299: @deffn Command {show ipv6 route} {}
300: @end deffn
301:
302: @deffn Command {show interface} {}
303: @end deffn
304:
305: @deffn Command {show ip prefix-list [@var{name}]} {}
306: @end deffn
307:
308: @deffn Command {show route-map [@var{name}]} {}
309: @end deffn
310:
311: @deffn Command {show ip protocol} {}
312: @end deffn
313:
314: @deffn Command {show ipforward} {}
315: Display whether the host's IP forwarding function is enabled or not.
316: Almost any UNIX kernel can be configured with IP forwarding disabled.
317: If so, the box can't work as a router.
318: @end deffn
319:
320: @deffn Command {show ipv6forward} {}
321: Display whether the host's IP v6 forwarding is enabled or not.
322: @end deffn
323:
324: @deffn Command {show zebra fpm stats} {}
325: Display statistics related to the zebra code that interacts with the
326: optional Forwarding Plane Manager (FPM) component.
327: @end deffn
328:
329: @deffn Command {clear zebra fpm stats} {}
330: Reset statistics related to the zebra code that interacts with the
331: optional Forwarding Plane Manager (FPM) component.
332: @end deffn
FreeBSD-CVSweb <freebsd-cvsweb@FreeBSD.org>
![[BACK]](/icons/cvsweb/back.gif){kind=icon}
Return to main.texi CVS log ![[TXT]](/icons/cvsweb/text.gif){kind=icon}
![[DIR]](/icons/cvsweb/dir.gif){kind=icon}
Up to [ELWIX - Embedded LightWeight unIX -] / embedaddon / quagga / doc