Screen OS

Hello,

I have an SSG5 that has a deviec in the DMZ that needs to access devices in our trusted network, and needs to be accessed form anywhere in the untrusted.

I've been following articles and trying sop many different things that I think I have gone in circles, and need help.

I have tried MIP, VIP, swithched interfaces between routing and NAT.

Here is my config, please point out any glaring errors:

Thanks!

set clock timezone 0
set vrouter trust-vr sharable
set vrouter "untrust-vr"
exit
set vrouter "trust-vr"
unset auto-route-export
exit
set service "fakewebport" protocol tcp src-port 0-65525 dst-port 4568-4568
unset alg rtsp enable
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 name ""
set admin password ""
set admin manager-ip
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
set zone "DMZ" tcp-rst
set zone "VLAN" block
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 "Null"
set interface "wireless0/0" zone "Null"
set interface "bgroup0" zone "Trust"
set interface "bgroup1" zone "DMZ"
set interface bgroup1 port ethernet0/1
set interface bgroup1 port ethernet0/2
set interface bgroup1 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 50.x.x.9/29
set interface ethernet0/0 route
set interface bgroup0 ip 10.4.100.253/24
set interface bgroup0 nat
set interface bgroup1 ip 10.4.150.1/24
set interface bgroup1 nat
set interface ethernet0/0 gateway 50.x.x.14
set interface bgroup1 mtu 1500
unset interface vlan1 bypass-others-ipsec
unset interface vlan1 bypass-non-ip
set interface ethernet0/0 ip manageable
set interface bgroup0 ip manageable
unset interface bgroup1 ip manageable
set interface ethernet0/0 manage ping
set interface ethernet0/0 manage ssh
set interface ethernet0/0 manage web
set interface bgroup0 manage mtrace
set interface ethernet0/0 vip 50.x.x.12 80 "HTTP" 10.4.150.100
set interface ethernet0/2 dhcp client enable
unset interface ethernet0/2 dhcp client settings update-dhcpserver
set interface "ethernet0/0" mip 50.x.x.12 host 10.4.150.100 netmask 255.255.255.255 vr "trust-vr"
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 address "Trust" "10.4.0.0/16" 10.4.0.0 255.255.0.0
set address "Trust" "10.4.150.100/255.255.255.255" 10.4.150.100 255.255.255.255
set address "Untrust" "207.x.x.x/255.255.255.248" 207.x.x.x 255.255.255.248
set address "Untrust" "SUPP NAT" 173.x.x.209 255.255.255.255
set address "Untrust" "USER2" 198.x.x.128 255.255.255.224
set address "DMZ" "10.4.150.0/24" 10.4.150.0 255.255.255.0
set address "DMZ" "10.4.150.100/32" 10.4.150.100 255.255.255.255
set group address "Untrust" "USER"
set group address "Untrust" "USER" add "207.x.x.x/255.255.255.248"
set group address "Untrust" "USER" add "SUPP NAT"
set group address "Untrust" "USER" add "USER2"
set group service "DMZ HTTP"
set group service "DMZ HTTP" add "fakewebport"
set group service "DMZ HTTP" add "HTTP"
set group service "DMZ HTTP" add "HTTPS"
set group service "DMZ HTTP" add "ICMP-ANY"
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 policy id 2 name "Decoders_to_int" from "DMZ" to "Trust" "10.4.150.0/24" "10.4.0.0/16" "PING" permit log
set policy id 2
set service "RTSP"
exit
set policy id 3 name "Trust-DMZ all traffic" from "Trust" to "DMZ" "10.4.0.0/16" "10.4.150.0/24" "ANY" permit log
set policy id 3
exit
set policy id 7 name "decoder access" from "Untrust" to "DMZ" "Any" "VIP(50.x.x.12)" "HTTP" permit log
set policy id 7
exit
set nsmgmt bulkcli reboot-timeout 60
set ssh version v2
set ssh enable
set config lock timeout 5
unset license-key auto-update
set wlan 0 channel auto
set wlan 1 channel auto
set wlan 0 transmit power minimum
set wlan 1 transmit power minimum
set wlan acl mode strict
set snmp port listen 161
set snmp port trap 162
set vrouter "untrust-vr"
exit
set vrouter "trust-vr"
unset add-default-route
set route 10.4.0.0/16 interface bgroup0 gateway 10.4.100.1 permanent
exit
set vrouter "untrust-vr"
exit
set vrouter "trust-vr"
exit

Hi,

You have configured no default route.

set vrouter "trust-vr"
set route 0.0.0.0/0 interface ethernet0/0 gateway 5.x.x.y

exit

save

Hello,

I see you have configured both VIP and MIP for the same IP

set interface ethernet0/0 vip 50.x.x.12 80 "HTTP" 10.4.150.100
set interface "ethernet0/0" mip 50.x.x.12 host 10.4.150.100 netmask 255.255.255.255 vr "trust-vr"

Since MIP wil always take precedence so I would suggest remove VIP and keep only MIP. Also update the policy too.

Rest if it still doesnt work then please collect the debugs and share them here

clear db

set ff src-ip x.x.x.x dst-ip y.y.y.y

set ff src-ip y.y.y.y dst-ip x.x.x.x

debug flow basic

initiate the non-working traffic

undebug all

get db st

======================================================================

Regards

Sarab

sarab,

Thank you for the suggestions, I followed them, here are the results:

****** 944781.0: <Untrust/ethernet0/0> packet received [52]******
ipid = 4654(122e), @032dc3d0
other ip packet handle.
****** 944781.0: <Untrust/ethernet0/0> packet received [52]******
ipid = 4655(122f), @032dcbd0
other ip packet handle.
****** 944781.0: <Untrust/ethernet0/0> packet received [52]******
ipid = 4658(1232), @032dd3d0
other ip packet handle.
****** 944784.0: <Untrust/ethernet0/0> packet received [52]******
ipid = 4660(1234), @032ddbd0
other ip packet handle.
****** 944784.0: <Untrust/ethernet0/0> packet received [52]******
ipid = 4661(1235), @032de3d0
other ip packet handle.
****** 944784.0: <Untrust/ethernet0/0> packet received [52]******
ipid = 4662(1236), @032debd0
other ip packet handle.
****** 944790.0: <Untrust/ethernet0/0> packet received [48]******
ipid = 4701(125d), @032df3d0
other ip packet handle.
****** 944790.0: <Untrust/ethernet0/0> packet received [48]******
ipid = 4702(125e), @032dfbd0
other ip packet handle.
****** 944790.0: <Untrust/ethernet0/0> packet received [48]******
ipid = 4704(1260), @032e03d0
other ip packet handle.

Thank you for any help you can give me.

following that, I did a snoop, and got this:

945213.0: ethernet0/0(i) len=66:b89bc9daf38a->00408ccfc059/0800
173.x.x.49 -> 50.x.x.12/6
vhl=45, tos=20, id=7618, frag=4000, ttl=123 tlen=52
tcp:ports 58508->80, seq=4145901041, ack=0, flag=8002/SYN

the 00408ccfc059 MAC address is that of the device in the DMZ, the b89bc9daf38a is the MAC of the gateway device.

It appears the MIP may be wrong?

I would say that  173.x.x.49 does not have its gateway set to the SSG5, that its ARP is not resolving to the firewalls mac address.

the debug "other ip packet handle" means that the firewall is ignoring the packet since the dst-mac address is not for itself.

Regards,

Sam

The 173. address is my network, at a different office. (I am trying to get to it from the Internet side).

Correction --  the gateway device with MAC address b89bc9daf38a (I assume 50.x.x.14? "get arp" will confirm), does not have the correct MAC address for SSG5's eth0/0.

Sorry for not having read your previous posts correctly.

Regards,

Sam

Hi,

Please try this:

1. Enable the logging at session start in the MIP/VIP policies.

2. Write down the MAC-address of 10.4.150.100

3. Ping 10.4.150.100 from the firewall.

4. Type get arp. Is the IP correctly resolved to its MAC?

5. Try to connect to the MIP/VIP from Internet before the arp cache entry has expired. Do you see any policy hits in the traffic log?

Could you please try clearing the Arp on the upstream gateway device or just reboot it so that the learnt MAC is cleared and then try connecting to MIP/VIP.

Regards

Sarab

sarab,

It appears your suggestion worked, I can now access the device remotely.

I'm not sure exactly why that should've worked (ARP sholuld have cleared itself many times over the 12 days I've been dealing with it).

Thank you very much!

I am glad the issue is fixed.

It happens because of some bug in that upstream device that it could not clear the cached ARP entry. And reboot cleared the cache and issue was fixed.

echidov, Thank you for your input, I tried that, but it did not seem to help.

I overlooked that, because in the GUI, it had that route in there: (it's in twice now that I added it via CLI).

The bottom one was in there before.