1478
C
HAPTER
79: MPLS L3VPN C
ONFIGURATION
belong to the same OSPF domain, and the route advertisement between them
should use Type 3 LSAs (inter-provider routes).
To solve the above problems, PE uses an extended BGP/OSPF interaction process
called BGP/OSPF interoperability to advertise routes from one site to another,
differentiating the routes from real AS-External routes. The process requires that
extended BGP community attributes carry the information for identifying the OSPF
attributes.
It is required that each OSPF domain has a configurable domain ID. It is
recommended to configure for all OSPF instances in the network related to each
VPN instance the same domain ID, or adopt the default ID. Thus, the system can
know that all VPN routes with the same domain ID are from the same VPN
instance.
3
Routing loop detection
If OSPF runs between CEs and PEs and a VPN site is connected to multiple PEs,
when a PE advertises the BGP VPN routes learnt from MPLS/BGP to the VPN site
through LSAs, the LSAs may be received by another PE, resulting in a routing loop.
To avoid routing loops, when creating Type 3 LSAs, the PE always sets the flag bit
DN for BGP VPN routes learnt from MPLS/BGP, regardless of whether the PE and
the CEs are connected through the OSPF backbone. When performing route
calculation, the OSPF process of the PE ignores the Type 3 LSAs whose DN bit is
set.
If the PE needs to advertise to a CE the routes from other OSPF domains, it must
indicate that it is the ASBR, and advertise the routes using Type 5 LSAs.
Sham link
Generally, BGP peers carry routing information on the MPLS VPN backbone
through the BGP extended community attributes. The OSPF that runs on the
remote PE can use the information to create Type 3 summary LSAs to be
transmitted to the CEs. As shown in
Figure 420
, both site 1 and site 3 belong to
VPN 1 and OSPF area1. They are connected to different PEs, PE 1 and PE 2. There
is an intra-area OSPF link called backdoor link between them. In this case, the
route connecting the two sites through PEs is an inter-area route. It is not preferred
by OSPF because its preference is lower than that of the intra-area route across the
backdoor link.
Содержание MSR 50 Series
Страница 152: ...152 CHAPTER 5 ATM CONFIGURATION...
Страница 209: ...Troubleshooting 209 Use the debugging dialer event and debugging dialer packet commands to locate the problem...
Страница 210: ...210 CHAPTER 6 DCC CONFIGURATION...
Страница 234: ...234 CHAPTER 7 DLSW CONFIGURATION...
Страница 344: ...344 CHAPTER 14 X 25 AND LAPB CONFIGURATION...
Страница 350: ...350 CHAPTER 15 LINK AGGREGATION OVERVIEW...
Страница 358: ...358 CHAPTER 17 MODEM CONFIGURATION...
Страница 486: ...486 CHAPTER 23 MSTP CONFIGURATION...
Страница 506: ...506 CHAPTER 25 VOICE VLAN CONFIGURATION...
Страница 510: ...510 CHAPTER 26 PORT ISOLATION CONFIGURATION...
Страница 524: ...524 CHAPTER 27 DYNAMIC ROUTE BACKUP CONFIGURATION...
Страница 538: ...538 CHAPTER 28 LOGICAL INTERFACE CONFIGURATION...
Страница 548: ...548 CHAPTER 29 CPOS INTERFACE CONFIGURATION...
Страница 572: ...572 CHAPTER 32 DHCP OVERVIEW...
Страница 604: ...604 CHAPTER 36 DHCP SNOOPING CONFIGURATION...
Страница 608: ...608 CHAPTER 37 BOOTP CLIENT CONFIGURATION...
Страница 646: ...646 CHAPTER 42 IP UNICAST POLICY ROUTING CONFIGURATION...
Страница 650: ...650 CHAPTER 43 UDP HELPER CONFIGURATION...
Страница 738: ...738 CHAPTER 50 IPV6 UNICAST POLICY ROUTING CONFIGURATION...
Страница 770: ...770 CHAPTER 51 TERMINAL ACCESS CONFIGURATION...
Страница 798: ...798 CHAPTER 52 FEP INSTALLATION AND CONFIGURATION...
Страница 808: ...808 CHAPTER 53 TERMINAL ACCESS TROUBLESHOOTING...
Страница 814: ...814 CHAPTER 54 TERMINAL ACCESS FAQ...
Страница 824: ...824 CHAPTER 55 IP ROUTING OVERVIEW...
Страница 876: ...876 CHAPTER 56 BGP CONFIGURATION...
Страница 916: ...916 CHAPTER 57 IS IS CONFIGURATION...
Страница 970: ...970 CHAPTER 58 OSPF CONFIGURATION...
Страница 1006: ...1006 CHAPTER 60 ROUTING POLICY CONFIGURATION...
Страница 1013: ...Configuration Example 1013 3 1 ms 1 ms 1 ms 1 1 2 2 Trace complete...
Страница 1014: ...1014 CHAPTER 61 STATIC ROUTING CONFIGURATION...
Страница 1048: ...1048 CHAPTER 63 IPV6 IS IS CONFIGURATION...
Страница 1068: ...1068 CHAPTER 64 IPV6 OSPFV3 CONFIGURATION...
Страница 1080: ...1080 CHAPTER 65 IPV6 RIPNG CONFIGURATION...
Страница 1114: ...1114 CHAPTER 68 MULTICAST ROUTING AND FORWARDING CONFIGURATION...
Страница 1160: ...1160 CHAPTER 70 MSDP CONFIGURATION...
Страница 1234: ...1234 CHAPTER 73 MLD CONFIGURATION...
Страница 1278: ...1278 CHAPTER 74 IPV6 PIM CONFIGURATION...
Страница 1310: ...1310 CHAPTER 75 MULTICAST VPN CONFIGURATION...
Страница 1344: ...1344 CHAPTER 76 MPLS BASICS CONFIGURATION...
Страница 1458: ...1458 CHAPTER 78 MPLS L2VPN CONFIGURATION...
Страница 1555: ...MPLS L3VPN Configuration Example 1555 5 packet s received 0 00 packet loss round trip min avg max 66 79 109 ms...
Страница 1556: ...1556 CHAPTER 79 MPLS L3VPN CONFIGURATION...
Страница 1588: ...1588 CHAPTER 80 DVPN CONFIGURATION...
Страница 1648: ...1648 CHAPTER 85 QOS POLICY CONFIGURATION...
Страница 1696: ...1696 CHAPTER 89 MPLS QOS CONFIGURATION...
Страница 1708: ...1708 CHAPTER 90 DAR CONFIGURATION...
Страница 1728: ...1728 CHAPTER 91 FRAME RELAY QOS CONFIGURATION...
Страница 1750: ...1750 CHAPTER 92 802 1X CONFIGURATION...
Страница 1788: ...1788 CHAPTER 93 AAA RADIUS HWTACACS CONFIGURATION...
Страница 1810: ...1810 CHAPTER 95 MAC AUTHENTICATION CONFIGURATION...
Страница 1850: ...1850 CHAPTER 97 PKI CONFIGURATION...
Страница 1872: ...1872 CHAPTER 98 PORTAL CONFIGURATION...
Страница 1970: ...1970 CHAPTER 106 BACKUP CENTER CONFIGURATION...
Страница 2048: ...2048 CHAPTER 110 NETSTREAM CONFIGURATION...
Страница 2084: ...2084 CHAPTER 112 RMON CONFIGURATION...
Страница 2094: ...2094 CHAPTER 113 SNMP CONFIGURATION...
Страница 2114: ...2114 CHAPTER 115 FTP CONFIGURATION...
Страница 2123: ...System Maintaining Example 2123 The above output shows that nine routers are involved from the source to the destination device...
Страница 2124: ...2124 CHAPTER 117 SYSTEM MAINTAINING AND DEBUGGING...
Страница 2154: ...2154 CHAPTER 119 INFORMATION CENTER CONFIGURATION...
Страница 2170: ...2170 CHAPTER 121 MAC ADDRESS TABLE MANAGEMENT CONFIGURATION...
Страница 2186: ...2186 CHAPTER 123 POE CONFIGURATION...
Страница 2198: ...2198 CHAPTER 125 ACFP CONFIGURATION...
Страница 2206: ...2206 CHAPTER 126 ACSEI CONFIGURATION...
Страница 2216: ...2216 CHAPTER 127 TRACK CONFIGURATION...
Страница 2232: ...2232 CHAPTER 128 IPX CONFIGURATION...
Страница 2242: ...2242 CHAPTER 129 VOICE OVERVIEW...
Страница 2244: ...2244 CHAPTER 130 VOIP OVERVIEW...
Страница 2288: ...2288 CHAPTER 132 VOICE ENTITY CONFIGURATION...
Страница 2342: ...2342 CHAPTER 134 E1 AND T1 CONFIGURATION...
Страница 2354: ...2354 CHAPTER 135 FAX OVER IP CONFIGURATION...
Страница 2366: ...2366 CHAPTER 136 H 323 CONFIGURATION...
Страница 2384: ...2384 CHAPTER 137 SIP OVERVIEW...