Re: Display of bridge member interfaces cut short - bug or intention?

From: DtxdF <DtxdF_at_disroot.org>
Date: Wed, 20 Dec 2023 20:55:30 UTC
Hi Patrick,

I have opened a bug in BugZilla [1] some time ago, it seems to be related.

Truncating the output can be a problem with automation tools that rely on the output of ifconfig(8) to perform some tasks.

[1] https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=275491

El 20 de diciembre de 2023 5:04:36 p. m. UTC, "Patrick M. Hausen" <hausen@punkt.de> escribió:
>Hi all,
>
>as some probably know we provide web hosting services and we use jails for that.
>
>On some particular host we have 255 vnet jails all of which are connected to the
>external interface of the host - renamed to "inet0" in our environment - via
>if_bridge(4) and all managed with iocage.
>
>root@ph003:~ # grep inet0 /iocage/jails/vpro*/config.json|wc -l
>     255
>
>Of these 251 also have a second epair interface connected to a private bridge
>named "priv1". These are used for connections to the central database server
>which should not be exposed to the Internet.
>
>root@ph003:~ # grep priv1 /iocage/jails/vpro*/config.json | wc -l
>     251
>
>While looking for a different problem to my great suprise I found today that
>ifconfig truncates the list of member interfaces for both bridge instances.
>And both to the same value of 102, although the member numbers are (albeit slightly)
>different:
>
>root@ph003:~ # ifconfig inet0|grep member:|wc -l
>     102
>root@ph003:~ # ifconfig priv1 | grep member: | wc -l
>     102
>
>All 255 jails are connected to the external network and perfectly reachable from
>the Internet. That's why I conclude that the display is wrong, not the bridge
>configuration.
>
>What's happening here? Is this intentional or shall I file a bug report?
>
>More importantly: either way is this only cosmetic or will we hit another unexpected
>limit of the number of interfaces that can be members of a bridge any time soon?
>
>Kind regards,
>Patrick
>-- 
>punkt.de GmbH
>Patrick M. Hausen
>infrastructure
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