Date: Tue, 11 Mar 2014 22:06:28 GMT From: Adam McDougall <mcdouga9@egr.msu.edu> To: freebsd-gnats-submit@FreeBSD.org Subject: conf/187457: ifconfig IP range assignment too restrictive Message-ID: <201403112206.s2BM6SEf085651@cgiserv.freebsd.org> Resent-Message-ID: <201403112210.s2BMA0V3031586@freefall.freebsd.org>
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>Number: 187457 >Category: conf >Synopsis: ifconfig IP range assignment too restrictive >Confidential: no >Severity: non-critical >Priority: low >Responsible: freebsd-bugs >State: open >Quarter: >Keywords: >Date-Required: >Class: change-request >Submitter-Id: current-users >Arrival-Date: Tue Mar 11 22:10:00 UTC 2014 >Closed-Date: >Last-Modified: >Originator: Adam McDougall >Release: FreeBSD 10.0-STABLE >Organization: >Environment: FreeBSD build10 10.0-STABLE FreeBSD 10.0-STABLE #0 r262298: Fri Feb 21 18:28:26 EST 2014 root@build10:/usr/obj/usr/src/sys/BUILD10 amd64 >Description: Recently I came up with the need to assign almost every IP in a /24 subnet to an interface. I wanted to avoid 250+ lines in /etc/rc.conf so I read the rc.conf manpage and discovered the wonderful range feature where I thought I could use: ifconfig_lagg0_alias0="inet 10.0.30.2-254/24" I found out it only creates addresses up to around .34 and prints "Range specification is too large", all as an anti foot-shooting protection due to _IPEXPANDMAX=31 in /etc/network.subr. Could the code be changed to allow for example a whole /24 to be created with a single range? Looking at SVN, this appears to apply to 9 as well. Workaround: define a bunch of smaller ranges: ifconfig_lagg0_aliases="inet 10.0.30.2-31/24 inet 10.0.30.32-63/32 \ inet .... etc etc" >How-To-Repeat: Try to set a large range in /etc/rc.conf and reboot. ifconfig_interfacename0="up" ifconfig_interfacename0_alias0="inet 10.0.30.2-254/24" >Fix: Raise _IPEXPANDMAX=31 in network.subr? Untested but seems logical since the only apparent purpose is to prevent accidental misconfiguration. It is easy to see if the range is defined too large then it might make a poor choice regarding broadcast IPs, oversized netmasks or something. I didn't check exactly how many IPs it assigned, it should be near 32. I was in a rush and had to settle for a workaround that evening. >Release-Note: >Audit-Trail: >Unformatted:
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