Dell S4048T-ON, Configuration Manual

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3 Prepend "65001 65002" to as-path.
Local-AS is prepended before the route-map to give an impression that update passed through a router in AS 200 before it reached Router
B.
BGP4 Management Information Base (MIB)
The FORCE10-BGP4-V2-MIB enhances support for BGP management information base (MIB) with many new simple network
management protocol (SNMP) objects and notifications (traps) defined in
draft-ietf-idr-bgp4-mibv2-05 . To see these enhancements,
download the MIB from the Dell website.
NOTE: For the Force10-BGP4-V2-MIB and other MIB documentation, refer to the Dell iSupport web page.
Important Points to Remember
• Because eBGP packets are not controlled by the ACL, packets from BGP neighbors cannot be blocked using the
deny ip
command.
• The f10BgpM2AsPathTableEntry table, f10BgpM2AsPathSegmentIndex , and f10BgpM2AsPathElementIndex are used to retrieve a
particular ASN from the AS path. These indices are assigned to the AS segments and individual ASN in each segment starting from 0.
For example, an AS path list of {200 300 400} 500 consists of two segments: {200 300 400} with segment index 0 and 500 with
segment index 1. ASN 200, 300, and 400 are assigned 0, 1, and 2 element indices in that order.
• Unknown optional transitive attributes within a given path attribute (PA) are assigned indices in order. These indices correspond to the
f10BgpM2PathAttrUnknownIndex field in the f10BgpM2PathAttrUnknownEntry table.
• Negotiation of multiple instances of the same capability is not supported. F10BgpM2PeerCapAnnouncedIndex and
f10BgpM2PeerCapReceivedIndex are ignored in the peer capability lookup.
• Configure inbound BGP soft-reconfiguration on a peer for f10BgpM2PrefixInPrefixesRejected to display the number of prefixes filtered
due to a policy. If you do enable
BGP soft-reconfig
, the denied prefixes are not accounted for.
• F10BgpM2AdjRibsOutRoute stores the pointer to the NLRI in the peer's Adj-Rib-Out.
• PA Index ( f10BgpM2PathAttrIndex field in various tables) is used to retrieve specific attributes from the PA table. The Next-Hop, RR
Cluster-list, and Originator ID attributes are not stored in the PA Table and cannot be retrieved using the
index passed in
command. These fields are not populated in f10BgpM2PathAttrEntry , f10BgpM2PathAttrClusterEntry , and
f10BgpM2PathAttrOriginatorIdEntry .
• F10BgpM2PathAttrUnknownEntry contains the optional-transitive attribute details.
• Query for f10BgpM2LinkLocalNextHopEntry returns the default value for Link-local Next-hop.
• RFC 2545 and the f10BgpM2Rfc2545Group are not supported.
• An SNMP query displays up to 89 AS paths. A query for a larger AS path count displays as "…" at the end of the output.
• SNMP set for BGP is not supported. For all peer configuration tables ( f10BgpM2PeerConfigurationGroup ,
f10BgpM2PeerRouteReflectorCfgGroup , and f10BgpM2PeerAsConfederationCfgGroup ), an SNMP set operation returns an error. Only
SNMP queries are supported. In addition, the f10BgpM2CfgPeerError , f10BgpM2CfgPeerBgpPeerEntry , and
f10BgpM2CfgPeerRowEntryStatus fields are to hold the SNMP set status and are ignored in SNMP query.
• The AFI/SAFI is not used as an index to the f10BgpM2PeerCountersEntry table. The BGP peer’s AFI/ SAFI (IPv4 Unicast or IPv6
Multicast) is used for various outbound counters. Counters corresponding to IPv4 Multicast cannot be queried.
• The f10BgpM2[Cfg]PeerReflectorClient field is populated based on the assumption that route-reflector clients are not in a full mesh if
you enable
BGP client-2-client reflection
and that the BGP speaker acting as reflector advertises routes learned from one
client to another client. If disabled, it is assumed that clients are in a full mesh and there is no need to advertise prefixes to the other
clients.
• High CPU utilization may be observed during an SNMP walk of a large BGP Loc-RIB.
• To avoid SNMP timeouts with a large-scale configuration (large number of BGP neighbors and a large BGP Loc-RIB), Dell Networking
recommends setting the timeout and retry count values to a relatively higher number. For example, t = 60 or r = 5.
• To return all values on an snmpwalk for the f10BgpM2Peer sub-OID , use the
-C c
option, such as
snmpwalk -v 2c -C c -c
public<IP_address><OID>
.
• An SNMP walk may terminate pre-maturely if the index does not increment lexicographically. Dell Networking recommends using
options to ignore such errors.
190 Border Gateway Protocol IPv4 (BGPv4)