R3#debug ip bgp BGP debugging is on for address family: IPv4 Unicast R3#clear ip bgp * R3# *Mar 1 02:11:24.015: BGPNSF state: 192.168.23.2 went from nsf_not_active to nsf_not_active *Mar 1 02:11:24.019: BGP: 192.168.23.2 went from Established to Idle *Mar 1 02:11:24.019: %BGP-5-ADJCHANGE: neighbor 192.168.23.2 Down User reset *Mar 1 02:11:24.023: BGP: 192.168.23.2 closing *Mar 1 02:11:24.027: BGP: 192.168.23.2 went from Idle to Active *Mar 1 02:11:24.039: BGP: 192.168.23.2 open active, local address 192.168.23.3 *Mar 1 02:11:24.111: BGP: 192.168.23.2 went from Active to OpenSent *Mar 1 02:11:24.111: BGP: 192.168.23.2 sending OPEN, version 4, my as: 65501, holdtime 180 seconds *Mar 1 02:11:24.111: BGP: 192.168.23.2 send message type 1, length (incl. header) 45 *Mar 1 02:11:24.167: BGP: 192.168.23.2 rcv message type 1, length (excl. header) 26 *Mar 1 02:11:24.167: BGP: 192.168.23.2 rcv OPEN, version 4, holdtime 180 seconds *Mar 1 02:11:24.167: BGP: 192.168.23.2 rcv OPEN w/ OPTION parameter len: 16 *Mar 1 02:11:24.167: BGP: 192.168.23.2 rcvd OPEN w/ optional parameter type 2 (Capability) len 6 *Mar 1 02:11:24.167: BGP: 192.168.23.2 OPEN has CAPABILITY code: 1, length 4 *Mar 1 02:11:24.167: BGP: 192.168.23.2 OPEN has MP_EXT CAP for afi/safi: 1/1 *Mar 1 02:11:24.167: BGP: 192.168.23.2 rcvd OPEN w/ optional parameter type 2 (Capability) len 2 *Mar 1 02:11:24.167: BGP: 192.168.23.2 OPEN has CAPABILITY code: 128, length 0 *Mar 1 02:11:24.167: BGP: 192.168.23.2 OPEN has ROUTE-REFRESH capability(old) for all address-families *Mar 1 02:11:24.167: BGP: 192.168.23.2 rcvd OPEN w/ optional parameter type 2 (Capability) len 2 *Mar 1 02:11:24.167: BGP: 192.168.23.2 OPEN has CAPABILITY code: 2, length 0 *Mar 1 02:11:24.167: BGP: 192.168.23.2 OPEN has ROUTE-REFRESH capability(new) for all address-families BGP: 192.168.23.2 rcvd OPEN w/ remote AS 65501 *Mar 1 02:11:24.167: BGP: 192.168.23.2 went from OpenSent to OpenConfirm *Mar 1 02:11:24.167: BGP: 192.168.23.2 went from OpenConfirm to Established *Mar 1 02:11:24.167: %BGP-5-ADJCHANGE: neighbor 192.168.23.2 Up
用 Loopback 来建立 iBGP Peers
在一个 AS 当中,除了 BGP 之外,一般会使用 IGP (例如:OSPF, EIGRP) 来作路由交换,在这个情况下,我们会使用 Loopback interface 作为 iBGP 的 neighbor address。因为 Loopback interface 永远是 UP 的,而且 Neighbor 之间可以自己通过 IGP 来寻找到达 Loopback 的路径,这比起使用 Interface IP 来作 neighbor address 来得灵活一点,也减少了因为 Interface down 而令 BGP Table 不稳定。
hostname Firewall ! interface Ethernet0/0 ip address 10.1.1.2 255.255.255.0 ! interface Ethernet0/1 ip address 10.2.2.2 255.255.255.0
在 R1 测试一下,明明可以 PING 到 10.2.2.1,就是没法建立 BGP Peers:
R1
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R1#ping 10.2.2.1
Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 10.2.2.1, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 40/50/72 ms R1#show ip bgp summary BGP router identifier 10.1.1.1, local AS number 65500 BGP table version is 1, main routing table version 1
Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd 10.2.2.1 4 65501 31 32 0 0 0 00:02:05 Idle
先在 R1 用 show ip route 确认一下 1.1.1.0/24 出现在 Routeing table 之中。
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R1#show ip route
<Output Omitted>
C 192.168.12.0/24 is directly connected, Ethernet0/0 1.0.0.0/24 is subnetted, 1 subnets C 1.1.1.0 is directly connected, Loopback0
然后使用 show ip bgp,可以看到 1.1.1.0/24 已经加入 BGP Table 了。
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R1#show ip bgp
<Output Omitted>
Network Next Hop Metric LocPrf Weight Path *> 1.1.1.0/24 0.0.0.0 0 32768 i
再来看看 R2 的 show ip bgp,有收到 1.1.1.0/24,而且 show ip route 也看到这网段已成功加入在 Route Table 之中!
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R2#show ip bgp
<Output Omitted>
Network Next Hop Metric LocPrf Weight Path *> 1.1.1.0/24 192.168.12.1 0 0 65100 i
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R2#show ip route
<Output Omitted>
C 192.168.12.0/24 is directly connected, Ethernet0/0 1.0.0.0/24 is subnetted, 1 subnets B 1.1.1.0 [20/0] via 192.168.12.1, 00:08:35 C 192.168.23.0/24 is directly connected, Ethernet0/1
R3 的情况又怎样呢?
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R3#show ip bgp
<Output Omitted>
Network Next Hop Metric LocPrf Weight Path *> 1.1.1.0/24 192.168.23.2 0 65200 65100 i R3#show ip route
<Output Omitted>
1.0.0.0/24 is subnetted, 1 subnets B 1.1.1.0 [20/0] via 192.168.23.2, 00:16:04 C 192.168.23.0/24 is directly connected, Ethernet0/1
就是一个 Network 指令,便完成了这个简单的 BGP 网络路由交换了。在此我们先解释一下在 show ip bgp 中看到的栏位都代表什么意思?
Network 网段的 Network ID 与及 Prefix Length。
Next Hop 要到达这个网段的 Next Hop IP address。如果显示为 0.0.0.0,即是说此网段是由本地 Router 发布的。另外有一个重要的地方要注意,就是此栏位所显示的 Next Hop IP 必需有路由可到达,此网段才会放入 Routing Table 之中,暂时请稍稍记一下,稍后的例子会加以说明。
Path 到达这个网段所经过的 AS Number,如果该网段是在本机的 AS Number 之中,此值便会变成空白,请留意是空白,并非 i ,i 是下一个栏位 Origin。
Origin Origin 并没有在栏位名显示出来,Origin 的值就显示在 Path 属性后面,只有三个值:i , e 或是 ?
i 此 Route 的来源是 IGP 或者是用 Network 指令
e 此 Route 的来源是 EGP,不过 EGP 已经是历史的产物,可以不用理会了。
? 此 Route 是通过 redistribute 得来的
Origin 也是选择最佳路径的一个方法,在稍后会详细说明。
Next-hop-self 指令
现在我们试试另一个例子:
R1 与 R2 是 eBGP,R2 与 R3 是 iBGP,R3 与 R4 是 eBGP。假设全部 IP 及 Peers 已经设置好,我们在 R1 设置 Loopback Interface 然后把它发布出去。看看 R2 的 BGP database,有 > 标记表示 BGP 选好了用 Next Hop IP 192.168.12.1 来到达 1.1.1.0/24,Route Table 也似乎没问题。
R2
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R2#show ip bgp
<Output Omitted>
Network Next Hop Metric LocPrf Weight Path *> 1.1.1.0/24 192.168.12.1 0 0 65100 i R2#show ip route
<Output Omitted>
C 192.168.12.0/24 is directly connected, Ethernet0/0 1.0.0.0/24 is subnetted, 1 subnets B 1.1.1.0 [20/0] via 192.168.12.1, 00:07:37 C 192.168.23.0/24 is directly connected, Ethernet0/1
R3(config)#ip route 192.168.12.1 255.255.255.255 ethernet 0/1 R3(config)#do sh ip route
<Output Omitted>
192.168.12.0/32 is subnetted, 1 subnets S 192.168.12.1 is directly connected, Ethernet0/1 1.0.0.0/24 is subnetted, 1 subnets B 1.1.1.0 [200/0] via 192.168.12.1, 00:00:04 C 192.168.23.0/24 is directly connected, Ethernet0/1 C 192.168.34.0/24 is directly connected, Ethernet0/0
另一个方法是使用 Next-hop-self 指令,迫使 R2 在发布 Route 给 R3 时使用自己的 IP 作为 Next Hop IP。只要在 BGP config 中加入一句 neighbor [IP] next-hop-self 便可以了。
现在我们再看看 R3 的 BGP Table,Next Hop 变成 192.168.23.2 了,有 > 标记,证明 BGP 接受了这条为 Best Path,Route Table 亦成功加入这条 Route。
R3
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R3#show ip bgp
<Output Omitted>
Network Next Hop Metric LocPrf Weight Path *>i1.1.1.0/24 192.168.23.2 0 100 0 65100 i
R3
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R3#show ip route
<Output Omitted>
1.0.0.0/24 is subnetted, 1 subnets B 1.1.1.0 [200/0] via 192.168.23.2, 00:02:47 C 192.168.23.0/24 is directly connected, Ethernet0/1 C 192.168.34.0/24 is directly connected, Ethernet0/0
R2#show ip bgp <Output Omitted> Network Next Hop Metric LocPrf Weight Path *> 1.1.1.0/24 192.168.12.1 0 0 65100 i
R5 收到但没有 > 标记,所以没有发布出去:
R5
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R5#show ip bgp <Output Omitted> Network Next Hop Metric LocPrf Weight Path * i1.1.1.0/24 2.2.2.2 0 100 0 65100 i
为什么没有发布呢?因为 IGP 「看不懂」 1.1.1.0/24
R5
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R5# show ip route
<--Output Omitted-->
2.0.0.0/32 is subnetted, 1 subnets O 2.2.2.2 [110/21] via 192.168.45.4, 00:37:38, Ethernet0/1 [110/21] via 192.168.35.3, 00:37:38, Ethernet0/0 C 192.168.45.0/24 is directly connected, Ethernet0/1 O 192.168.24.0/24 [110/20] via 192.168.45.4, 00:37:38, Ethernet0/1 5.0.0.0/24 is subnetted, 1 subnets C 5.5.5.0 is directly connected, Loopback0 C 192.168.56.0/24 is directly connected, Ethernet0/2 O 192.168.23.0/24 [110/20] via 192.168.35.3, 00:37:38, Ethernet0/0 C 192.168.35.0/24 is directly connected, Ethernet0/0
R5#show ip protocols *** IP Routing is NSF aware ***
Routing Protocol is "bgp 65125" Outgoing update filter list for all interfaces is not set Incoming update filter list for all interfaces is not set IGP synchronization is disabled Automatic route summarization is disabled Neighbor(s): Address FiltIn FiltOut DistIn DistOut Weight RouteMap 192.168.15.1 192.168.25.2 192.168.35.3 Maximum path: 1 Routing Information Sources: Gateway Distance Last Update 192.168.35.3 20 00:02:10 Distance: external 20 internal 200 local 200
所以根据概率程序选了 Next-hop 192.168.25.2 为 Best Path。
R5
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R5#show ip bgp BGP table version is 5, local router ID is 192.168.35.5 Status codes: s suppressed, d damped, h history, * valid, > best, i - internal, r RIB-failure, S Stale, m multipath, b backup-path, f RT-Filter, x best-external, a additional-path, c RIB-compressed, Origin codes: i - IGP, e - EGP, ? - incomplete RPKI validation codes: V valid, I invalid, N Not found
Network Next Hop Metric LocPrf Weight Path * 172.16.4.0/24 192.168.35.3 0 65001 i * 192.168.15.1 0 65001 i *> 192.168.25.2 0 65001 i
R5#show ip bgp BGP table version is 6, local router ID is 192.168.35.5 Status codes: s suppressed, d damped, h history, * valid, > best, i - internal, r RIB-failure, S Stale, m multipath, b backup-path, f RT-Filter, x best-external, a additional-path, c RIB-compressed, Origin codes: i - IGP, e - EGP, ? - incomplete RPKI validation codes: V valid, I invalid, N Not found
Network Next Hop Metric LocPrf Weight Path *m 172.16.4.0/24 192.168.35.3 0 65001 i *m 192.168.15.1 0 65001 i *> 192.168.25.2 0 65001 i
R5#show ip route 172.16.4.0 Routing entry for 172.16.4.0/24 Known via "bgp 65005", distance 20, metric 0 Tag 65001, type external Last update from 192.168.25.2 00:05:20 ago Routing Descriptor Blocks: * 192.168.35.3, from 192.168.35.3, 00:05:20 ago Route metric is 0, traffic share count is 1 AS Hops 1 Route tag 65001 MPLS label: none 192.168.25.2, from 192.168.25.2, 00:05:20 ago Route metric is 0, traffic share count is 1 AS Hops 1 Route tag 65001 MPLS label: none 192.168.15.1, from 192.168.15.1, 00:05:20 ago Route metric is 0, traffic share count is 1 AS Hops 1 Route tag 65001 MPLS label: none
R5#show ip route 172.16.4.0 Routing entry for 172.16.4.0/24 Known via "bgp 65005", distance 20, metric 0 Tag 65001, type external Last update from 192.168.25.2 00:00:19 ago Routing Descriptor Blocks: * 192.168.35.3, from 192.168.35.3, 00:00:19 ago Route metric is 0, traffic share count is 37 AS Hops 1 Route tag 65001 MPLS label: none 192.168.25.2, from 192.168.25.2, 00:00:19 ago Route metric is 0, traffic share count is 240 AS Hops 1 Route tag 65001 MPLS label: none 192.168.15.1, from 192.168.15.1, 00:00:19 ago Route metric is 0, traffic share count is 240 AS Hops 1 Route tag 65001 MPLS label: none
以上只是部份比较常用的 Best Path 机制,如果希望了解到更多,你可以到 这里 查看更详细的教学。
R2#show ip bgp 1.1.1.0 BGP routing table entry for 1.1.1.0/24, version 2 Paths: (1 available, best #1, table Default-IP-Routing-Table) Not advertised to any peer 65000 192.168.12.1 from 192.168.12.1 (192.168.12.1) Origin IGP, metric 0, localpref 100, valid, external, best
hostname R1 ! router bgp 65000 network 1.1.1.0 mask 255.255.255.0 neighbor 192.168.12.2 remote-as 65001 neighbor 192.168.12.2 send-community neighbor 192.168.12.2 route-map SetComm out ! access-list 1 permit 1.1.1.0 0.0.0.255 ! route-map SetComm permit 10 match ip address 1 set community 1000
现在看看 R2 的 Prefix 1.1.1.0,发现多了一行 Community 显示值为 1000。
R2
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R2#show ip bgp 1.1.1.0 BGP routing table entry for 1.1.1.0/24, version 2 Paths: (1 available, best #1, table Default-IP-Routing-Table) Flag: 0x820 Not advertised to any peer 65000 192.168.12.1 from 192.168.12.1 (192.168.12.1) Origin IGP, metric 0, localpref 100, valid, external, best Community: 1000
于是,我们就可以在 R2 使用 Community List 和 Route Map 配合一起做些事情。
例如我们想把 Community 是 1000 的 prefix 的 Local Preference 改成 500。
hostname R2 ! router bgp 65001 neighbor 192.168.12.1 remote-as 65000 neighbor 192.168.12.1 route-map SetLocal in no auto-summary ! ip community-list 1 permit 1000 ! route-map SetLocal permit 10 match community 1 set local-preference 500 R2#show ip bgp BGP table version is 2, local router ID is 192.168.12.2 Status codes: s suppressed, d damped, h history, * valid, > best, i - internal, r RIB-failure, S Stale Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path *> 1.1.1.0/24 192.168.12.1 0 500 0 65000 i
另外,利用 Community 也能做一些 Route Filtering 的动作。
Community 的值除了可以自己设置外,其实系统有 4 个预设值可以使用,分别是:no-advertise,local-AS,no-export 和 internet,4 个预设值的作用如下:
Keywords
功能
no-advertise
告诉收到这条 Prefix 的 Router 不要将这条 Prefix 发布出去
local-AS
告诉收到这条 Prefix 的 Router 这条 Prefix 只能发布给 Confederation 中的同一个 AS
R2#show ip bgp 1.1.1.0 BGP routing table entry for 1.1.1.0/24, version 2 Paths: (1 available, best #1, table Default-IP-Routing-Table, not advertised to any peer) Not advertised to any peer Local, (Received from a RR-client) 192.168.12.1 from 192.168.12.1 (4.4.4.4) Origin IGP, metric 0, localpref 100, valid, confed-internal, best Community: no-advertise R2#show ip bgp 2.2.2.0 BGP routing table entry for 2.2.2.0/24, version 3 Paths: (1 available, best #1, table Default-IP-Routing-Table, not advertised outside local AS) Advertised to update-groups: 1 Local, (Received from a RR-client) 192.168.12.1 from 192.168.12.1 (4.4.4.4) Origin IGP, metric 0, localpref 100, valid, confed-internal, best Community: local-AS R2#show ip bgp 3.3.3.0 BGP routing table entry for 3.3.3.0/24, version 4 Paths: (1 available, best #1, table Default-IP-Routing-Table, not advertised to EBGP peer) Advertised to update-groups: 1 Local, (Received from a RR-client) 192.168.12.1 from 192.168.12.1 (4.4.4.4) Origin IGP, metric 0, localpref 100, valid, confed-internal, best Community: no-export R2#show ip bgp 4.4.4.0 BGP routing table entry for 4.4.4.0/24, version 5 Paths: (1 available, best #1, table Default-IP-Routing-Table) Advertised to update-groups: 1 Local, (Received from a RR-client) 192.168.12.1 from 192.168.12.1 (4.4.4.4) Origin IGP, metric 0, localpref 100, valid, confed-internal, best Community: internet
R3#show ip bgp BGP table version is 4, local router ID is 192.168.34.3 Status codes: s suppressed, d damped, h history, * valid, > best, i - internal, r RIB-failure, S Stale Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path *>i2.2.2.0/24 192.168.12.1 0 100 0 i *>i3.3.3.0/24 192.168.12.1 0 100 0 i *>i4.4.4.0/24 192.168.12.1 0 100 0 i
在 R4 查看 BGP Table,发现没有收到 2.2.2.0/24,因为 R3 看见 Prefix 的 Community 是 local-AS,这条 Prefix 只能存在于 Confederation 的 Local AS 之中,R4 位于另一个 AS,因此 R3 不把这条 Prefix 发出去。
R4
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R4#show ip bgp BGP table version is 3, local router ID is 192.168.45.4 Status codes: s suppressed, d damped, h history, * valid, > best, i - internal, r RIB-failure, S Stale Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path *> 3.3.3.0/24 192.168.34.3 0 100 0 (10) i *> 4.4.4.0/24 192.168.34.3 0 100 0 (10) i
最后,在 R5 不会看到 3.3.3.0/24,因为这条 Prefix 的 Community 是 no-export,因此 R4 不会发给位于其他 AS 之内的 R5。至于 4.4.4.0/24 的 Community 是 internet 则没有此限制。
R5
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R5#show ip bgp BGP table version is 2, local router ID is 192.168.45.5 Status codes: s suppressed, d damped, h history, * valid, > best, i - internal, r RIB-failure, S Stale Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path *> 4.4.4.0/24 192.168.45.4 0 65000 i
R1#show ip bgp BGP table version is 8, local router ID is 192.168.12.1 Status codes: s suppressed, d damped, h history, * valid, > best, i - internal, r RIB-failure, S Stale, m multipath, b backup-path, f RT-Filter, x best-external, a additional-path, c RIB-compressed, Origin codes: i - IGP, e - EGP, ? - incomplete RPKI validation codes: V valid, I invalid, N Not found
Network Next Hop Metric LocPrf Weight Path *>i 10.0.0.0/24 192.168.12.2 0 100 0 65023 1000 2000 i *>i 10.0.0.0/23 192.168.12.2 0 100 0 i *>i 10.0.1.0/24 192.168.12.2 0 100 0 65023 2000 4000 i
R1#show ip bgp BGP table version is 8, local router ID is 192.168.12.1 Status codes: s suppressed, d damped, h history, * valid, > best, i - internal, r RIB-failure, S Stale, m multipath, b backup-path, f RT-Filter, x best-external, a additional-path, c RIB-compressed, Origin codes: i - IGP, e - EGP, ? - incomplete RPKI validation codes: V valid, I invalid, N Not found
Network Next Hop Metric LocPrf Weight Path *>i 10.0.0.0/23 192.168.12.2 0 100 0 i
R1#show ip bgp BGP table version is 8, local router ID is 192.168.12.1 Status codes: s suppressed, d damped, h history, * valid, > best, i - internal, r RIB-failure, S Stale, m multipath, b backup-path, f RT-Filter, x best-external, a additional-path, c RIB-compressed, Origin codes: i - IGP, e - EGP, ? - incomplete RPKI validation codes: V valid, I invalid, N Not found
Network Next Hop Metric LocPrf Weight Path *>i 10.0.0.0/23 192.168.12.2 0 100 0 i *>i 10.0.1.0/24 192.168.12.2 0 100 0
留意 Summary Route 失去了 AS Path 信息,AS Path 是防止 Route Loop 的机制,建议在 aggregate-address 增加 as-set 选项保留 AS Path 信息。
R1#show ip bgp BGP table version is 15, local router ID is 192.168.12.1 Status codes: s suppressed, d damped, h history, * valid, > best, i - internal, r RIB-failure, S Stale, m multipath, b backup-path, f RT-Filter, x best-external, a additional-path, c RIB-compressed, Origin codes: i - IGP, e - EGP, ? - incomplete RPKI validation codes: V valid, I invalid, N Not found
Network Next Hop Metric LocPrf Weight Path *>i 10.0.0.0/23 192.168.12.2 0 100 0 {65023,1000,3000,2000,4000} i
留意 as-set 除了保留 AS Path 信息,也帮 Summary Route 继承了所有 Community 属性。
R1
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R1#show ip bgp 10.0.0.0/23 BGP routing table entry for 10.0.0.0/23, version 25 Paths: (1 available, best #1, table default, not advertised to EBGP peer) Not advertised to any peer Refresh Epoch 2 {65023,1000,3000,2000,4000}, (aggregated by 65012 192.168.23.2) 192.168.12.2 from 192.168.12.2 (192.168.23.2) Origin IGP, metric 0, localpref 100, valid, internal, best Community: no-export local-AS rx pathid: 0, tx pathid: 0x0
如果不想继承所有 Community 属性,可以使用 advertise-map 去帮 Summary Route 选择继承那一条 Route 的属性。
R1#show ip bgp BGP table version is 6, local router ID is 1.1.1.1 Status codes: s suppressed, d damped, h history, * valid, > best, i - internal, r RIB-failure, S Stale Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path r> 2.2.2.0/24 192.168.13.3 0 65001 i
R1#show ip eigrp topology IP-EIGRP Topology Table for AS(1)/ID(1.1.1.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply, r - reply Status, s - sia Status
P 2.2.2.0/24, 1 successors, FD is 409600 via 192.168.12.2 (409600/128256), Ethernet0/0 P 192.168.12.0/24, 1 successors, FD is 281600 via Connected, Ethernet0/0
R1#show ip route | begin Gateway Gateway of last resort is not set
C 192.168.12.0/24 is directly connected, Ethernet0/0 1.0.0.0/24 is subnetted, 1 subnets C 1.1.1.0 is directly connected, Loopback0 C 192.168.13.0/24 is directly connected, Ethernet0/1 2.0.0.0/24 is subnetted, 1 subnets B 2.2.2.0 [20/0] via 192.168.13.3, 00:00:02
R1(config)#router bgp 65000 R1(config-router)#network 2.2.2.0 mask 255.255.255.0 backdoor R1(config-router)#end R1#show ip route | begin Gateway Gateway of last resort is not set
C 192.168.12.0/24 is directly connected, Ethernet0/0 1.0.0.0/24 is subnetted, 1 subnets C 1.1.1.0 is directly connected, Loopback0 C 192.168.13.0/24 is directly connected, Ethernet0/1 2.0.0.0/24 is subnetted, 1 subnets D 2.2.2.0 [90/409600] via 192.168.12.2, 00:00:22, Ethernet0/0