IP Configuration: SLA
Overview
Cisco Sx350, SG350X, SG350XG, Sx550X & SG550XG Series Managed Switches, Firmware Release 2.2.5.x
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A track object status can be used by various applications in decisions that require knowledge
of network connectivity. One example of such an application is VRRP. The track object is
assigned to a VRRP router. If track status is down, the VRRP priority of router is decremented
by a value defined by user. If track status is up, the original VRRP priority of router is
maintained.
The following describes the main terms used in this section:
•
Operation—
Each IP SLAs ICMP Echo operation sends a single ICMP Echo request
to a target address at a configured frequency rate. It then waits for a response.
•
Track Object State
—Each tracking object maintains an operation state. The state is
either:
Up
or
Down
. After object creation, the state is set to
Up
. The following table
specifies the conversion of the IP SLAs operation return code to the object state:
NOTE
If the IP SLAs operation specified by the track argument is not configured or is
its schedule is
pending
, its state is OK.
NOTE
An application that is bound to a non-existing tracking object will receive the
Up
state.
•
SLA Operation State
—This can be either
Scheduled
, which means the operation
begins immediately or
Pending
, which means it has been created but not activated.
•
Timeout value —
Specifies the interval time of waiting for the ICMP echo reply
message or an ICMP error message.
•
Return Code—
After an operation has been finished the operation return code is set
according to the following:
-
ICMP Echo reply has been received—Return code is set to
OK
.
-
ICMP Error reply has been received—Return code is set to
error
.
-
No any ICMP reply has been received—Return code is set to
error
.
-
Configured Source IP address or Source interface is not accessible—Return code is
set to
error
.
•
Tracker
—Tracks the results of operations.
Operation Return Code
Track Operation State
OK
Up
Error
Down