RE: [fw-wiz] [fw-wiz]: unable to ping internet servers

From: Steven Alexander (alexander.s_at_mccd.edu)
Date: 06/02/03

  • Next message: Noonan, Wesley: "RE: [fw-wiz] pix vs. ios firewall feature set"
    To: "Hilal Hussein" <hilalma@hotmail.com>, <Wesley_Noonan@bmc.com>, <avraham@jct.ac.il>, <firewall-wizards@icsalabs.com>
    Date: Mon, 2 Jun 2003 09:33:28 -0700
    

    You have to allow inbound ICMP echo-reply packets. ICMP isn't
    connection oriented so the incoming echo-reply is not known to be part
    of the same sequence of events as the earlier outgoing echo-request.

    -steven

    -----Original Message-----
    From: Hilal Hussein [mailto:hilalma@hotmail.com]
    Sent: Sunday, June 01, 2003 8:07 AM
    To: Wesley_Noonan@bmc.com; avraham@jct.ac.il;
    firewall-wizards@icsalabs.com
    Subject: [fw-wiz] [fw-wiz]: unable to ping internet servers

    Dear Gentlemen,

    I have a PIX 520 Firewall with

    global (outside) 1 1.2.3.4
    nat (inside) 1 0.0.0.0 0.0.0.0 0 0
    static (inside,outside) 11.22.33.44 172.17.1.10 netmask 255.255.255.255
    0 0 conduit permit gre host 11.22.33.44 host 55.66.77.88 conduit permit
    icmp any any outbound 10 permit 172.17.0.0 255.255.0.0 0 tcp outbound
    10 permit 172.17.0.0 255.255.0.0 0 udp outbound 10 permit 172.17.0.0
    255.255.0.0 0 icmp apply (inside) 10 outgoing_src

    we are accessing the internet having direct connection from the firewall
    to
    the ISP Router. and all internal users have the Firewall as the internet

    Gateway.

    Questions
    why internal users can't ping www.yahoo.com or even the ip address of
    yahoo
    server or any internet server, at the same time I can do the ping from
    the
    firewall itself - ping outside 64.58.76.224 ?

    Do i need to do any changes in the firewall ? since conduit permit icmp
    any
    any & outbound 10 permit 172.17.0.0 255.255.0.0 0 icmp which should be
    allowed bidirectional ICMP traffic between our internal network
    (172.17.0.0
    - 255.255.0.0).

    hopefully i am clear in describing the problem, your comments and
    support
    are highly appreciated,

    With regards,

    Hilal Hussein

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  • Next message: Noonan, Wesley: "RE: [fw-wiz] pix vs. ios firewall feature set"

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