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bshiers
New Member
March 28, 2018
Question

Issues talking to routes learned through OSPF.

  • March 28, 2018
  • 8 replies
  • 10922 views

I have a Fortinet 60C running the most recent firmware available for it.  I have setup OSPF to a Cisco 2821 router in my lab.  OSPF comes up and I exchange routes, however I am unable to communicate from my LAN to the learned routes.  The fortinet will pass them no issues.  here is the pertinent config: 

 

edit "internal" set vdom "root" set ip 192.168.7.254 255.255.255.0 set allowaccess ping https ssh http fgfm capwap set type physical set snmp-index 6

 

config router access-list edit "OSPF_List" config rule edit 1 set prefix 192.168.48.0 255.255.255.0 set exact-match enable next end next end

 

config router ospf set distance-external 105 set distance-inter-area 100 set default-information-originate always set router-id 192.168.7.254 config area edit 0.0.0.0 set authentication md5 next end config ospf-interface edit "Internal_OSPF_Interface" set interface "internal" set authentication md5 set md5-key 1 "ENC eTcVX9pm00rCTASSzXmuPpA5KZZU" set dead-interval 40 set hello-interval 10 next end config network edit 1 set prefix 192.168.7.0 255.255.255.0 next end config redistribute "connected" set status enable end config redistribute "static" set status enable end config redistribute "rip" end config redistribute "bgp" end config redistribute "isis" end

 

get router info ospf route C 192.168.7.0/24 [1] is directly connected, internal, Area 0.0.0.0 O 192.168.48.0/24 [2] via 192.168.7.2, internal, Area 0.0.0.0 O 192.168.49.0/24 [2] via 192.168.7.2, internal, Area 0.0.0.0

 

From the fortinet: 

 

execute ping 192.168.48.1 PING 192.168.48.1 (192.168.48.1): 56 data bytes 64 bytes from 192.168.48.1: icmp_seq=2 ttl=255 time=10.7 ms 64 bytes from 192.168.48.1: icmp_seq=3 ttl=255 time=0.5 ms

 

I traceroute from a PC on the 192.168.7.x block as I can't ping 192.168.48.1: 

 

Brandons-iMac:~ brandon$ traceroute 192.168.48.1 traceroute to 192.168.48.1 (192.168.48.1), 64 hops max, 52 byte packets 1 192.168.7.254 (192.168.7.254) 0.655 ms 0.468 ms 0.400 ms 2 216.67.149.25 (216.67.149.25) 22.135 ms 15.943 ms 15.826 ms

 

It hits the forinet and routes out my default WAN gateway instead of my LAN/Internal interface:

 

From the Cisco I can ping the internal interface on the fortinet:

 

Border-Router#ping Protocol [ip]: Target IP address: 192.168.7.254 Repeat count [5]: Datagram size [100]: Timeout in seconds [2]: Extended commands : y Source address or interface: 192.168.48.1 Type of service [0]: Set DF bit in IP header? [no]: Validate reply data? [no]: Data pattern [0xABCD]: Loose, Strict, Record, Timestamp, Verbose[none]: Sweep range of sizes : Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 192.168.7.254, timeout is 2 seconds: Packet sent with a source address of 192.168.48.1 !!!!!

 

I can't ping the PC, which does allow PING from the LAN:

 

Border-Router#ping Protocol [ip]: Target IP address: 19 %Error opening t[link]ftp://255.255.255.255/network-confg[/link] (Timed out)2.168. *Mar 28 12:11:56.787: %SYS-4-CONFIG_RESOLVE_FAILURE: System config parse from (t[link]ftp://255.255.255.255/network-confg)[/link] failed7.119 Repeat count [5]: Datagram size [100]: Timeout in seconds [2]: Extended commands : y Source address or interface: 192.168.48.1 Type of service [0]: Set DF bit in IP header? [no]: Validate reply data? [no]: Data pattern [0xABCD]: Loose, Strict, Record, Timestamp, Verbose[none]: Sweep range of sizes : Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 192.168.7.119, timeout is 2 seconds: Packet sent with a source address of 192.168.48.1 ....

 

Here's the config on the Cisco: 

 

interface GigabitEthernet0/0 description to HomeLan ip address 192.168.7.2 255.255.255.0 ip ospf authentication message-digest ip ospf message-digest-key 1 md5 44Bottles!12 duplex auto speed auto ! interface GigabitEthernet0/1 description to Lab ip address 192.168.49.1 255.255.255.0 secondary ip address 192.168.48.1 255.255.255.0 duplex auto speed auto ! router ospf 1 router-id 192.168.7.2 redistribute connected subnets network 192.168.48.0 0.0.0.255 area 0 network 192.168.49.0 0.0.0.255 area 0 network 0.0.0.0 255.255.255.255 area 0

 

Any thoughts?  I'm sure it's something simple I'm missing and I can't find it!  I can talk to/from the fortinet to the routes learned on Gig0/1 via OSPF but I can't find my issue.  I did allow a rule to allow passing from internal to internal to both the netblocks on Gig0/1.  

    8 replies

    Toshi_Esumi
    SuperUser
    SuperUser
    March 28, 2018

    Try adding deny policy for those internal subnets (192.168.48.0/24 and 49/24) toward the internet interface and move it to the top of policies. So that the FG never try that path when OSPF with Cisco is down. I'm suspecting the PC has been sending packets toward the internal subnets before the FG has learned routes, and a session(s) is established toward the internet following the default route.

    bshiers
    bshiersAuthor
    New Member
    March 28, 2018

    Toshi,

     

    Thanks for the suggestion. I just tried it and the rule is catching traffic however I'm not getting anwhere with the block now: 

     

    --- 192.168.48.1 ping statistics --- 15 packets transmitted, 0 packets received, 100.0% packet loss Brandons-iMac:~ brandon$ traceroute 192.168.48.1 traceroute to 192.168.48.1 (192.168.48.1), 64 hops max, 52 byte packets 1 * * *

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