conf/151063: [rc.subr] Verify network link and packet flow before starting network services

[Jeremy Chadwick]

>Number:         151063
>Category:       conf
>Synopsis:       [rc.subr] Verify network link and packet flow before starting network services
>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:   Wed Sep 29 10:00:11 UTC 2010
>Closed-Date:
>Last-Modified:
>Originator:     Jeremy Chadwick
>Release:        FreeBSD 8.1-STABLE amd64
>Organization:
>Environment:
System: FreeBSD icarus.home.lan 8.1-STABLE FreeBSD 8.1-STABLE #0: Wed Sep 15 14:59:46 PDT 2010 root at icarus.home.lan:/usr/obj/usr/src/sys/X7SBA_RELENG_8_amd64 amd64
>Description:
	There's a long-standing issue that plagues both users and system administrators
	on FreeBSD: network services (named, ntpd, etc.) starting before the actual
	network layer is up and fully functional.  Monitoring link state according to
	ifconfig is not enough -- actual packet flow verification is needed.

	I've written a script along with the help of the community and Doug Barton
	to help alleviate this problem as best possible.  There are better solutions
	over the long-term, involving daemons which maintain/spawn services (think
	svcs(1) and svcadm(1M) on Solaris), but for now this should be sufficient.

	Original discussion thread:

	http://lists.freebsd.org/pipermail/freebsd-stable/2010-April/056400.html

	The script is in use by existing community users, and tested by a good number
	of people with complex network environments (dual NICs + vlan(4) + NAT) on
	both RELENG_7 and RELENG_8.  So far it has been used by placing the script
	into /usr/local/etc/rc.d followed by setting appropriate vars in /etc/rc.conf:

	http://jdc.parodius.com/freebsd/netwait

	Patches for rc.conf(5) man page and /etc/defaults/rc.conf:

	http://jdc.parodius.com/freebsd/netwait_patches/

	All of this should be reviewed by someone with familiarity with rc(8).
	Please CC Doug Barton <dougb at FreeBSD.org> as well.  Thanks!
>How-To-Repeat:
	n/a
>Fix:
	n/a
>Release-Note:
>Audit-Trail:
>Unformatted: