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From: Stephen Hemminger <stephen@networkplumber.org>
To: "Kai Hendry" <hendry@iki.fi>
Cc: netdev@vger.kernel.org
Subject: Re: Find IP address of active interface
Date: Mon, 25 Jul 2022 11:07:42 -0700	[thread overview]
Message-ID: <20220725110742.34650b91@hermes.local> (raw)
In-Reply-To: <c7aa5278-5c8d-4d76-96d7-bb52244786e9@www.fastmail.com>

On Mon, 25 Jul 2022 08:48:15 +0800
"Kai Hendry" <hendry@iki.fi> wrote:

> Is there an easier way than:
> 
> ip route get 8.8.8.8 2>/dev/null|grep -Eo 'src [0-9.]+'|grep -Eo '[0-9.]+'
> 
> To figure out the active, Internet routing interface?
> 
> Thank you,

Alternate:

$ ip -j route get 8.8.8.8 | \
  python3 -c 'import json,sys;obj=json.load(sys.stdin);print(obj[0]["dev"]);'
enp2s0

But both options won't do what you want if there is ECMP routes.

      reply	other threads:[~2022-07-25 18:07 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-07-25  0:48 Find IP address of active interface Kai Hendry
2022-07-25 18:07 ` Stephen Hemminger [this message]

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