3Com 4800G Series, Руководство по настройке

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Detecting Reachability of the Static Route’s Nexthop 253
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When configuring a static route, the static route does not take effect if you
specify the next hop address first and then configure it as the IP address of a
local interface, such as a VLAN interface.
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If you do not specify the preference when configuring a static route, the
default preference will be used. Reconfiguring the default preference applies
only to newly created static routes.
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You can flexibly control static routes by configuring tag values and using the
tag values in the routing policy.
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If the destination IP address and mask are both configured as 0.0.0.0 with the
ip route-static command, the route is the default route.
Detecting Reachability
of the Static Route’s
Nexthop
If a static route fails due to a topology change or a fault, the connection will be
interrupted. To improve network stability, the system needs to detect reachability
of the static route’s next hop and switch to a backup route once the next hop is
unreachable.
Detecting Nexthop
Reachability Through
Track
If you specify the nexthop but not outgoing interface when configuring a static
route, you can associate the static route with a track entry to check the static route
validity:
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When the track entry is positive, the static route’s nexthop is reachable and the
static route takes effect.
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When the track entry is negative, the static route’s nexthop is unreachable and
the static route is invalid. For details about track, refer to “Track Configuration”
on page 1237.
Network requirements
To detect the reachability of a static route’s nexthop through a Track entry, you
need to create a Track first. For detailed Track configuration procedure, refer to
“Track Configuration Task List” on page 1238.
Configuration procedure
Follow these steps to detect the reachability of a static route’s nexthop through
Track:
Configure a static
route ip route-static dest-address { mask |
mask-length } { next-hop-address |
interface-type interface-number
[ next-hop-address ] } [ preference
preference-value ] [ tag tag-value ]
[ description description-text ]
Required
By default, preference
for static routes is 60,
tag is 0, and no
description information
is configured.
Configure the default
preference for static
routes ip route-static default-preference
default-preference-value
Optional
60 by default
To do… Use the command… Remarks
To do… Use the command… Remarks
Enter system view system-view -