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  • 1.  SSG-5 Static Routing, No Nat.... cannot ping router from DMZ or Trusted zone.

    Posted 05-27-2010 12:44

    I have a *PUBLIC* /26 IP address range which I am sub-dividing into /30, /30, /28, and /28 networks.

     

    The network diagram is a follows:

    ISP Router --(/30)--> Our Router --(/30)--> SSG-5 --(/28)--> DMZ

                                                                                     |-------(/28)-->Trusted

     

    The problem is that I cannot ping the inside interface of the router from the DMZ or Trusted zone (actually I can ping the router, and I see that the router receives the packets form its packet count, but they fail to route on return to the firewall).  However, If the zones/interfaces are set to use NAT, I can ping router.  Correct me if I am wrong but I should NOT have to use NAT, I am using all static routes and public IP address space.

     

    Any help would be greatly appreciated.

     

    Here is my configuration:

     

    unset key protection enable
    set clock timezone 0
    set vrouter trust-vr sharable
    set vrouter "untrust-vr"
    exit
    set vrouter "trust-vr"
    unset auto-route-export
    exit
    set alg appleichat enable
    unset alg appleichat re-assembly enable
    set alg sctp enable
    set auth-server "Local" id 0
    set auth-server "Local" server-name "Local"
    set auth default auth server "Local"
    set auth radius accounting port 1646
    set admin auth web timeout 10
    set admin auth dial-in timeout 3
    set admin auth server "Local"
    set admin format dos
    set zone "Trust" vrouter "trust-vr"
    set zone "Untrust" vrouter "trust-vr"
    set zone "DMZ" vrouter "trust-vr"
    set zone "VLAN" vrouter "trust-vr"
    set zone "Untrust-Tun" vrouter "trust-vr"
    set zone "Trust" tcp-rst
    set zone "Untrust" block
    unset zone "Untrust" tcp-rst
    set zone "MGT" block
    unset zone "V1-Trust" tcp-rst
    unset zone "V1-Untrust" tcp-rst
    set zone "DMZ" tcp-rst
    unset zone "V1-DMZ" tcp-rst
    unset zone "VLAN" tcp-rst
    set zone "Untrust" screen tear-drop
    set zone "Untrust" screen syn-flood
    set zone "Untrust" screen ping-death
    set zone "Untrust" screen ip-filter-src
    set zone "Untrust" screen land
    set zone "V1-Untrust" screen tear-drop
    set zone "V1-Untrust" screen syn-flood
    set zone "V1-Untrust" screen ping-death
    set zone "V1-Untrust" screen ip-filter-src
    set zone "V1-Untrust" screen land
    set interface "ethernet0/0" zone "Untrust"
    set interface "ethernet0/1" zone "DMZ"
    set interface "bgroup0" zone "Trust"
    set interface bgroup0 port ethernet0/2
    set interface bgroup0 port ethernet0/3
    set interface bgroup0 port ethernet0/4
    set interface bgroup0 port ethernet0/5
    set interface bgroup0 port ethernet0/6
    unset interface vlan1 ip
    set interface ethernet0/0 ip x.y.71.6/30
    set interface ethernet0/0 route
    set interface ethernet0/1 ip x.y.71.17/28
    set interface ethernet0/1 route
    set interface bgroup0 ip x.y.71.49/28
    set interface bgroup0 route
    set interface ethernet0/0 gateway x.y.71.5
    set interface ethernet0/0 gateway x.y.71.5
    set interface ethernet0/0 gateway x.y.71.5
    unset interface vlan1 bypass-others-ipsec
    unset interface vlan1 bypass-non-ip
    set interface ethernet0/0 ip manageable
    set interface ethernet0/1 ip manageable
    set interface bgroup0 ip manageable
    set interface bgroup0 manage mtrace
    set interface "serial0/0" modem settings "USR" init "AT&F"
    set interface "serial0/0" modem settings "USR" active
    set interface "serial0/0" modem speed 115200
    set interface "serial0/0" modem retry 3
    set interface "serial0/0" modem interval 10
    set interface "serial0/0" modem idle-time 10
    set flow tcp-mss
    unset flow tcp-syn-check
    unset flow tcp-syn-bit-check
    set flow reverse-route clear-text prefer
    set flow reverse-route tunnel always
    set pki authority default scep mode "auto"
    set pki x509 default cert-path partial
    set crypto-policy
    exit
    set ike respond-bad-spi 1
    set ike ikev2 ike-sa-soft-lifetime 60
    unset ike ikeid-enumeration
    unset ike dos-protection
    unset ipsec access-session enable
    set ipsec access-session maximum 5000
    set ipsec access-session upper-threshold 0
    set ipsec access-session lower-threshold 0
    set ipsec access-session dead-p2-sa-timeout 0
    unset ipsec access-session log-error
    unset ipsec access-session info-exch-connected
    unset ipsec access-session use-error-log
    set vrouter "untrust-vr"
    exit
    set vrouter "trust-vr"
    exit
    set url protocol websense
    exit
    set policy id 1 from "Trust" to "Untrust"  "Any" "Any" "ANY" permit
    set policy id 1
    exit
    set nsmgmt bulkcli reboot-timeout 60
    set ssh version v2
    set config lock timeout 5
    unset license-key auto-update
    set telnet client enable
    set snmp port listen 161
    set snmp port trap 162
    set vrouter "untrust-vr"
    exit
    set vrouter "trust-vr"
    unset add-default-route
    exit
    set vrouter "untrust-vr"
    exit
    set vrouter "trust-vr"
    exit


    #no
    #NAT
    #static
    #routing


  • 2.  RE: SSG-5 Static Routing, No Nat.... cannot ping router from DMZ or Trusted zone.

    Posted 05-27-2010 13:12

    You don't appear to have any policies to allow inter-zone traffic except from trust to untrust. So pings to/from trust to dmz will fail (Assuming I read your question correctly) without a policy.



  • 3.  RE: SSG-5 Static Routing, No Nat.... cannot ping router from DMZ or Trusted zone.

    Posted 05-27-2010 13:53

     


    @muttbarker wrote:

    You don't appear to have any policies to allow inter-zone traffic except from trust to untrust. So pings to/from trust to dmz will fail (Assuming I read your question correctly) without a policy.


     

    I am pinging from the Trust to the Router, (Trust -> Untrust -> Router, then the Router responds to the Untrust, which at this point it is lost / dropped).

     

    My configuration has an ANY ANY permit policy from Trust to Untrust (as shown above).

     

    I hope this clears it up.  For what its worth, I still added any any permit policies to DMZ to Trust, DMZ to untrust, and still the ping fails.

     

    I appreciate the help though!



  • 4.  RE: SSG-5 Static Routing, No Nat.... cannot ping router from DMZ or Trusted zone.
    Best Answer

    Posted 05-27-2010 15:56

    Looking at your config - you are trying to ping to 71.5 from 71.49 and the return fails - well one question I would have - do you have a route back to 71.49 specified on the 71.5. device? 

     

    Because looking at your config a ping from the trust zone to 71.5 is going to work fine from the SSG5 point of view. So the problem is not there. You could verify that with debug.

     

    When you use NAT the ping is sourced as coming from 71.6 so there is no issue with the return route. Not true when coming from 71.49. Make sense?

     



  • 5.  RE: SSG-5 Static Routing, No Nat.... cannot ping router from DMZ or Trusted zone.

    Posted 05-27-2010 17:15

     


    @muttbarker wrote:

    Looking at your config - you are trying to ping to 71.5 from 71.49 and the return fails - well one question I would have - do you have a route back to 71.49 specified on the 71.5. device? 

     

    Because looking at your config a ping from the trust zone to 71.5 is going to work fine from the SSG5 point of view. So the problem is not there. You could verify that with debug.

     

    When you use NAT the ping is sourced as coming from 71.6 so there is no issue with the return route. Not true when coming from 71.49. Make sense?

     


    Thank you for the explanation as to why the NAT worked and not the static routing, makes perfect sense.  I do have routes on the 71.5 Router, but it looks like I will have to revisit them; the problem is most likely there.  Debug did not show any traffic from the 71.5 src-ip. Thanks, you have been a big help.

     



  • 6.  RE: SSG-5 Static Routing, No Nat.... cannot ping router from DMZ or Trusted zone.

    Posted 05-28-2010 01:30

    Hi!

     

    Please ask your ISP if the router contains a static route for the  /26-network that points to the SSG5 untrust IP.

    The router is responding requests coming from its connected /30-network but does not know how to reach the rest of the /26-network.

     

    Kind regards,

    Edouard