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From: sean darcy <seandarcy2@gmail.com>
To: netfilter@vger.kernel.org
Subject: Re: does -p udp --dport 5060 not work with -j LOG?
Date: Thu, 01 May 2008 21:10:37 -0400	[thread overview]
Message-ID: <fvdpme$vrl$1@ger.gmane.org> (raw)
In-Reply-To: <1209689109.6381.20.camel@localhost.localdomain>

Diego Lacerda wrote:
> On Thu, 2008-05-01 at 16:53 -0700, Steven Kath wrote:
>>> There only one line in my script that uses SIP:
>>>
>>> grep SIP firewall-masq
>>> $IPT -t nat -A PREROUTING -i external -p udp  --dport 5060 -j LOG
>>> --log-prefix "SIP-BEFORE:  "
>>>
>>> And it's run first:
>>>
>>> sh -x firewall-masq
>>> + IPT=/sbin/iptables
>>> + /sbin/iptables -F
>>> + /sbin/iptables -X
>>> + /sbin/iptables -t nat -A PREROUTING -i external -p udp --dport 5060 -j
>>> LOG --log-prefix 'SIP-BEFORE:  '
>>> ...........
>>>
>>>
>>> I don't really understand this output:
>>>
>>> iptables -L -n -v -t nat | grep SIP
>>>      2   262 LOG        udp  --  *      *       0.0.0.0/0
>>> 0.0.0.0/0           udp dpt:5060 LOG flags 0 level 4 prefix `SIP-BEFORE:
>>> '
>>>   144K   24M LOG        udp  --  *      *       0.0.0.0/0
>>> 0.0.0.0/0           LOG flags 0 level 4 prefix `SIP-BEFORE:  '
>>> 41816 5117K LOG        udp  --  external *       0.0.0.0/0
>>> 0.0.0.0/0           LOG flags 0 level 4 prefix `SIP-BEFORE:  '
>>>      0     0 LOG        udp  --  external *       0.0.0.0/0
>>> 0.0.0.0/0           udp dpt:5060 LOG flags 0 level 4 prefix `SIP-BEFORE:
>>> '
>>>      0     0 LOG        udp  --  external *       0.0.0.0/0
>>> 0.0.0.0/0           udp dpt:5060 LOG flags 0 level 4 prefix `SIP-BEFORE:
>>> '
>> ...
>>
>> It looks like your nat table isn't getting flushed.  
>>
>> Have you tried running 'iptables -t nat -F' before firewall-masq or adding
>> that to the start of the script?
> 
> Yeah,
> 
> I think that you really need flush the NAT table before.
> In this case you can see that the second and third rules in you NAT table are logging every UDP packet (you can see that by first and second columns: packets/bytes).
> 
> Regards,
> 

Wow. That worked.

I always thought iptables -F flushed all the tables. Is there a command 
that does flush all the tables? Cleans the slate completely?

sean



  reply	other threads:[~2008-05-02  1:10 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-04-30 22:27 does -p udp --dport 5060 not work with -j LOG? sean darcy
2008-05-01  3:23 ` Diego Lacerda
2008-05-01 23:36   ` sean darcy
2008-05-01 23:53     ` Steven Kath
2008-05-02  0:45       ` Diego Lacerda
2008-05-02  1:10         ` sean darcy [this message]
2008-05-02  1:40           ` Steven Kath
2008-05-02 13:34           ` Jan Engelhardt

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