Brocade Network OS Administrator’s Guide v4.1.1 - Manual (Page 622)

messages. When two neighbors have different hold-time values, the lowest value is used. A hold-time
value of 0 means "always consider neighbor to be active."
BGP Identifier
Indicates the router (or device) ID of the sender. When router-id is not configured, device-id is taken
from the loopback interface. Otherwise, the lowest IP address in the system is used.
Parameter List
Optional list of additional parameters used in peer negotiation.
UPDATE message
The UPDATE message is used to advertise new routes, withdraw previously advertised routes, or
both.
WithdrawnRoutesLength WithdrawnRoutes Total PathAttributes Len Path Attributes NLRI
2 variable 2 variable variable
Withdrawn Routes Length
Indicates the length of next (withdrawn routes) field. It can be 0.
Withdrawn Routes
Contains list of routes (or IP-prefix/Length) to indicate routes being withdrawn.
Total Path Attribute Len
Indicates length of next (path attributes) field. It can be 0.
Path Attributes
Indicates characteristics of the advertised path. Possible attributes: Origin, AS Path, Next Hop, MED
(Multi-Exit Discriminator), Local Preference, Atomic Aggregate, Aggregator.
NLRI
Network Layer Reachability Information — the set of destinations whose addresses are represented
by one prefix. This field contains a list of IP address prefixes for the advertised routes.
NOTIFICATION message
In case of an error that causes the TCP connection to close, the closing peer sends a notification
message to indicate the type of error.
Error Code ErrorSubcode Error Data
1 1 variable
Error Code
Indicates the type of error, which can be one of following:
• Message header error
• Open message error
• Update message error
• Hold timer expired
UPDATE message
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