Extreme Networks ExtremeWare XOS 11.3, Руководство пользователя

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Status Monitoring and Statistics
ExtremeWare XOS 11.3 Concepts Guide
204
Each time a filter item is added to or deleted from a given filter, the specified events are compared
against the current configuration of the filter to try to logically simplify the configuration. Existing items
will be replaced by logically simpler items if the new item enables rewriting the filter. If the new item is
already included or excluded from the currently configured filter, the new item is not added to the filter.
Matching Expressions
You can configure the switch so messages reaching the target match a specified match expression. The
message text is compared with the configured match expression to determine whether to pass the
message on. To require that messages match a match expression, use the following command:
configure log target [console | memory-buffer | nvram | primary-msm | backup-msm |
session | syslog [all | <ipaddress> | <ipPort> {vr <vr_name>} [local0 ... local7]]]
match [any |<match-expression>]
The messages reaching the target will match the
match-expression
, a simple regular expression. The
formatted text string that makes up the message is compared with the match expression and is passed
to the target if it matches. This command does not affect the filter in place for the target, so the match
expression is compared only with the messages that have already passed the target’s filter. For more
information on controlling the format of the messages, see
“Formatting Event Messages” on page 206 .
Simple Regular Expressions. A simple regular expression is a string of single characters including the dot
character (.), which are optionally combined with quantifiers and constraints. A dot matches any single
character, while other characters match only themselves (case is significant). Quantifiers include the star
character (*) that matches zero or more occurrences of the immediately preceding token. Constraints
include the caret character (^) that matches at the beginning of a message and the currency character ($)
that matches at the end of a message. Bracket expressions are not supported. There are a number of
sources available on the Internet and in various language references describing the operation of regular
expressions.
Table 31 shows some examples of regular expressions.
Matching Parameters
Rather than using a text match, EMS allows you to filter more efficiently based on the parameter values
of the message. In addition to event components and conditions and severity levels, each filter item can
also use parameter values to further limit which messages are passed or blocked. The process of
creating, configuring, and using filters has already been described in
“Filtering By Components and
Conditions” on page 202 , so this section describes matching parameters with a filter item.
Table 31: Simple regular expressions
Regular Expression Matches Does Not Match
port port 2:3
import cars
portable structure poor
por
pot
..ar baar
bazaar
rebar bar
port.*vlan port 2:3 in vlan test
add ports to vlan
port/vlan
myvlan$ delete myvlan
error in myvlan myvlan port 2:3
ports 2:4,3:4 myvlan link down