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Date:      Sun, 1 Oct 2017 20:55:42 -0600
From:      The Doctor <doctor@doctor.nl2k.ab.ca>
To:        Polytropon <freebsd@edvax.de>
Cc:        freebsd-questions@freebsd.org
Subject:   Re: Weird turnoff
Message-ID:  <20171002025542.GA13466@doctor.nl2k.ab.ca>
In-Reply-To: <20171002023157.GA1163@doctor.nl2k.ab.ca>
References:  <20171001232531.GA18260@doctor.nl2k.ab.ca> <20171002021140.931f17de.freebsd@edvax.de> <20171002002506.GA42212@doctor.nl2k.ab.ca> <20171002041047.31f81a0d.freebsd@edvax.de> <20171002023157.GA1163@doctor.nl2k.ab.ca>

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On Sun, Oct 01, 2017 at 08:31:58PM -0600, The Doctor wrote:
> On Mon, Oct 02, 2017 at 04:10:47AM +0200, Polytropon wrote:
> > On Sun, 1 Oct 2017 18:25:06 -0600, The Doctor wrote:
> > > On Mon, Oct 02, 2017 at 02:11:40AM +0200, Polytropon wrote:
> > > > On Sun, 1 Oct 2017 17:25:31 -0600, The Doctor wrote:
> > > > > Could be an attack.
> > > > > 
> > > > > All right.
> > > > > 
> > > > > As of this morning (3 p.m. UTC) my seconday FreeBSD 11.1 server
> > > > > has been going intreface down then up and then unable to route.
> > > > > 
> > > > > Rebooted this system 2 times today.
> > > > > 
> > > > > 
> > > > > What should I bee looking for?
> > > > 
> > > > Primarily the system's log files in /var/log: messages, auth.log,
> > > > security. Also check the output of the periodic scripts (mailed
> > > > to root or another user), do they contain hints to something that
> > > > looks suspicious (SUID changes, system file modifications, etc.)?
> > > >
> > > 
> > > exactly what I am looking for
> > 
> > Many system actions are recorded in those log files. Of course
> > if an attacker has write access to them, it's fairly easy for
> > him to delete the entries which suggest that he has been there...
> > 
> > 
> > 
> > > I am going to have to do a transcribe as I am opreating from the
> > > potential victim and ssh'ing to this terminal
> > > 
> > > or ftp the information over
> > 
> > Use FTP only within a trusted network (which implies only trusted
> > participants), as information is typically transmitted without
> > encryption!
> > 
> > 
> > 
> > 
> > > Oct  1 16:56:46 gallifrey kernel: igb0: link state changed to DOWN
> > > Oct  1 17:00:10 gallifrey kernel: igb0: link state changed to UP
> > > Oct  1 17:17:32 gallifrey kernel: igb0: <Intel(R) PRO/1000 Network Connection, Version - 2.5.3-k> port 0x6020-0x603f mem 0xc7120000-0xc713ffff,0xc7144000-0xc7147fff irq 26 at device 0.0 numa-domain 0 on pci3
> > 
> > This looks like some reboot. The last message above usually is
> > the _first_ message with igb0 originator, the following ones
> > (the ones _above_ it!) must be from a previous run of the system.
> > A link change cannot be reported before the device hasn't been
> > initialized by the kernel.
> > 
> > >From your log, we can easily see the NIC init messages with
> > the following timestamps (summarized):
> > 
> > 	Oct  1 17:17:32 gallifrey kernel: igb0
> > 	Oct  1 17:17:32 gallifrey kernel: igb1
> > 
> > 	Oct  1 17:40:09 gallifrey kernel: igb0
> > 	Oct  1 17:40:09 gallifrey kernel: igb1
> > 
> > 	Oct  1 12:04:48 gallifrey kernel: igb0
> > 	Oct  1 12:04:48 gallifrey kernel: igb1
> > 
> > This looks like reboots. Does /var/log/messages have multiple
> > occurances of the FreeBSD "kernel banner" (the copyright
> > information and so on)?
> > 
> >
> 
> Just me resetting the system
> 
> > 
> > > Nothing in the auth.log that I can see as an issue.
> > 
> > That matches the reboot theory. A manual reboot (issued by a system
> > operator) would cause an entry, but an accidental reboot would not.
> > 
> > 
> > 
> > > Also, how do I turn routing / ifconfig back on?
> > 
> > You can use "service netif restart" to restart the networking
> > subsystem.
> >
> 
> That speeds the process up
> 

Or hinder.
Just did a manual test and now the server in
question cannot see outside the LAN.

> > 
> > 
> > > Rebooting is not that fun
> > 
> > Agreed, and it doesn't fix the problem either... :-)
> > 
> >
> 
> Back to square 1 - where to look for what shut the if down to start with
> 
> .
> 
> Also 
> 
> what sort of test can the server do to find that it cannot find he internet so that
> it can self restart ?
> 
> Say if ping 8.8.8.8 reurns error implement service netif restart ?
> 
> > 
> > 
> > -- 
> > Polytropon
> > Magdeburg, Germany
> > Happy FreeBSD user since 4.0
> > Andra moi ennepe, Mousa, ...
> > _______________________________________________
> > freebsd-questions@freebsd.org mailing list
> > https://lists.freebsd.org/mailman/listinfo/freebsd-questions
> > To unsubscribe, send any mail to "freebsd-questions-unsubscribe@freebsd.org"
> 
> -- 
> Member - Liberal International This is doctor@@nl2k.ab.ca Ici doctor@@nl2k.ab.ca
> Yahweh, Queen & country!Never Satan President Republic!Beware AntiChrist rising!
> https://www.empire.kred/ROOTNK?t=94a1f39b  Look at Psalms 14 and 53 on Atheism
> Talk Sense to a fool and he calls you foolish - Euripides
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-- 
Member - Liberal International This is doctor@@nl2k.ab.ca Ici doctor@@nl2k.ab.ca
Yahweh, Queen & country!Never Satan President Republic!Beware AntiChrist rising!
https://www.empire.kred/ROOTNK?t=94a1f39b  Look at Psalms 14 and 53 on Atheism
Talk Sense to a fool and he calls you foolish - Euripides



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