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From: Willy Tarreau <w@1wt.eu>
To: Thorsten Glaser <t.glaser@tarent.de>
Cc: Oleg <lego12239@yandex.ru>, netdev@vger.kernel.org
Subject: Re: ipv6 ::1 and lo dev
Date: Wed, 18 Aug 2021 22:17:55 +0200	[thread overview]
Message-ID: <20210818201755.GA4899@1wt.eu> (raw)
In-Reply-To: <fb3e3ad3-7bc3-9420-d3f6-e9bae91f4cd@tarent.de>

On Wed, Aug 18, 2021 at 07:47:37PM +0200, Thorsten Glaser wrote:
> On Wed, 18 Aug 2021, Oleg wrote:
> 
> > I try to replace ::1/128 ipv6 address on lo dev with ::1/112 to
> > access more than 1 address(like with ipv4 127.0.0.1/8). But i get
> 
> AIUI this is not possible in IPv6, only :: and ::1 are reserved,
> the rest of ::/96 is IPv4-compatible IPv6 addresses.
> 
> I never understood why you'd want more than one address for loopback
> anyway (in my experience, the more addresses a host has, the more
> confused it'll get about which ones to use for what).

It's because you've probably never dealt with massive hosting :-)
Sometimes binding a full /24 (or smaller) on the loopback, be it
for listening addresses or to be used as sources to connect to
next hops, is extremely useful.

Willy

  reply	other threads:[~2021-08-18 20:18 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-08-18 16:59 ipv6 ::1 and lo dev Oleg
2021-08-18 17:47 ` Thorsten Glaser
2021-08-18 20:17   ` Willy Tarreau [this message]
2021-08-18 21:15     ` Stephen Hemminger
2021-08-19  9:16   ` Oleg

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