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From: "Jee J.Z." <jz105@york.ac.uk>
To: netfilter@lists.netfilter.org
Subject: icmp echo reply && FORWARD chain
Date: Sun, 2 May 2004 15:24:47 +0100	[thread overview]
Message-ID: <006701c43051$39130ad0$68892090@grouse> (raw)

Hi all,

My rules on a gateway linux box (PC2) are set as follows:

Internet(PC1 and so on)-----------(eth0)-PC2-(eth1)-------------Internal
networks(PC3 and so on...)

iptables -F
iptables -F -t nat
iptables -I FORWARD -j QUEUE
iptables -t nat -A POSTROUTING -o eth0 -j SNAT --to global_ip
iptables -t nat -A PREROUTING -i eth1 -j DNAT --to 192.168.0.2

ICMP echo request packets from PC1 or PC3 to PC2 can be caught by the
FORWARD chain queuing to userspace, however, ICMP echo reply (in response to
ping request from PC2) packets from PC1 or PC3 to PC2 will be ignored by the
FORWARD chain. Is this a reasonable phenomenon? Could anyone tell me the
reasons? Thanks a lot in advance!

Cheers,
Jee



             reply	other threads:[~2004-05-02 14:24 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2004-05-02 14:24 Jee J.Z. [this message]
2004-05-02 14:46 ` icmp echo reply && FORWARD chain Antony Stone
2004-05-02 15:29   ` Jee J.Z.
2004-05-02 15:42     ` Antony Stone
2004-05-02 22:43       ` Jee J.Z.
2004-05-02 23:03         ` Antony Stone

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