Configuring Link Scan Mode
The link scan feature in NetVisor OS detects physical link state changes. NetVisor OS version 6.0.0 (and later) supports interrupt-based link state change detection, in addition to the software-based link scan mode available in the previous versions. The software-based link scan mode performs state polling to detect changes at regular configurable intervals. When the link scan mode is set to hardware, on the other hand, the software uses the interrupt infrastructure to provide an improved detection mechanism for link state changes.
You can configure the link scan mode and interval by using the system-settings-modify command:
|
system-settings-modify |
Use this command to modify system settings. |
|
linkscan-interval 10000..1000000 |
Specify the linkscan interval as a value between 10000 μs and 1000000 μs. The default value is 150000 μs. Note: This parameter is not applicable when the link scan mode is hardware. |
|
linkscan-mode software|hardware |
Specify the linkscan mode as hardware or software. Software linkscan mode is enabled by default. Note: Arista recommends software linkscan mode. |
For example, to enable interrupt-based link state change detection, use the command:
CLI (network-admin@switch) > system-settings-modify linkscan-mode hardware
To view the current configuration, use the command:
CLI (network-admin@switch) > system-settings-show format linkscan-mode
linkscan-mode: hardware
To modify the link scan interval used in software-based mode to 100,000 μs, enter the command:
CLI (network-admin@switch) > system-settings-modify linkscan-interval 100000
To view the details, enter the command:
CLI (network-admin@switch) > system-settings-show
switch: Leaf1
optimize-arps: off
lldp: on
policy-based-routing: off
optimize-nd: off
reactivate-mac: on
reactivate-vxlan-tunnel-mac: on
manage-unknown-unicast: off
manage-broadcast: off
auto-trunk: on
auto-host-bundle: off
cluster-active-active-routing: on
fast-route-download: off
fast-interface-lookup: on
routing-over-vlags: off
source-mac-miss: copy-to-cpu
igmp-snoop: use-l3
vle-tracking-timeout: 3
pfc-buffer-limit: 40%
cosq-weight-auto: off
port-cos-drop-stats-interval(s): disable
lossless-mode: off
snoop-query-stagger: no-stagger-queries
host-refresh: off
proxy-conn-retry: on
proxy-conn-max-retry: 3
proxy-conn-retry-interval: 500
manage-l2-uuc-drop: on
xcvr-link-debug: disable
fastpath-bfd: off
linkscan-interval: 100000
linkscan-mode: hardware
single-pass-flood: off
Note: To avoid flaps, the link scan mode must match on both the switch ports connected by a link.