List Network Adaptors


Is Network Interface Connected

cat /sys/class/net/wlan0/operstate

Indicates the interface operational state, possible values are: “unknown”, “notpresent”, “down”, “lowerlayerdown”, “testing”,”dormant”, “up”.”no such file or directory”

You can test for “up”.

cat /sys/class/net/wlan0/carrier

Will give a result of 0, 1 or a ‘no such file or directory’ error message.

NOTE – we have seen this commant return a ‘1’ when the WiFi adaptor is not actually connected (‘ip addr’ returns “wlan0: <NO-CARRIER,…”. In this instance cat /sys/class/net/wlan0/operstate returned “dormant”

Other commands


Restarting After Changes

See here.

We benefit hugely from resources on the web so we decided we should try and give back some of our knowledge and resources to the community by opening up many of our company’s internal notes and libraries through mini sites like this. We hope you find the site helpful.
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