We have 2 sites linked together with VPN tunnel (Fortigate 60C devices). On each site I have ESXi server with a couple of VMs. Normally, everything works fine.
Site 1 (S1) subnet is 192.168.254.0/24, with Machine A1, A2 on ESXi1
Site 2 (S2) subnet is 192.168.253.0/24, with Machine B1, B2 on ESXi2
All ping between those machines works normally through VPN tunnel.
Suddently, S1-A1 cannot ping S2-B1 anymore, but S2-B1 still ping S1-A1.
All pings (using IP addresses) accross all machines (VMs and ESXi) works except from S1-A1 -> S2-B1.
Traceroute results were:
S1-A1 -> S2-B1 -> through Internet (?????)
S1-A1 -> S2-B2 -> through VPN Tunnel
S2-B2 -> S1-A1 -> through VPN Tunnel
S1-A1 -> S2-ESXi2 -> through VPN Tunnel
Machine A1 is a Windows 2003 R2 – SP2. There is 5 IP addresses binded on the NIC. I tried to disable and enable the NIC but the network management stopped responding. Only a reboot fixed the problem.
route print did not change. Gateway is the same and no specific route to reach B2.
arp -a did not show anything related to 192.168.253.0/24.
I don't understand why S1-A1 -> S2-ESXi2 worked but but not S1-A1 -> S2-B1 because B2 (192.168.253.18) is running on ESXi2 (192.168.253.23).
Registry entry of the Network Interface
Windows Registry Editor Version 5.00
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\Interfaces\{0E114693-5FC8-4AA4-AB98-14CE43E24DE5}]
"UseZeroBroadcast"=dword:00000000
"EnableDeadGWDetect"=dword:00000001
"EnableDHCP"=dword:00000000
"IPAddress"=hex(7):31,00,39,00,32,00,2e,00,31,00,36,00,38,00,2e,00,32,00,35,00,\
34,00,2e,00,31,00,35,00,00,00,31,00,39,00,32,00,2e,00,31,00,36,00,38,00,2e,\
00,32,00,35,00,34,00,2e,00,31,00,32,00,00,00,31,00,39,00,32,00,2e,00,31,00,\
36,00,38,00,2e,00,32,00,35,00,34,00,2e,00,31,00,33,00,00,00,31,00,39,00,32,\
00,2e,00,31,00,36,00,38,00,2e,00,32,00,35,00,34,00,2e,00,31,00,35,00,31,00,\
00,00,31,00,39,00,32,00,2e,00,31,00,36,00,38,00,2e,00,32,00,35,00,34,00,2e,\
00,34,00,30,00,00,00,00,00
which is 192.168.254.15 192.168.254.12 192.168.254.13 192.168.254.151 192.168.254.40
"SubnetMask"=hex(7):32,00,35,00,35,00,2e,00,32,00,35,00,35,00,2e,00,32,00,35,\
00,35,00,2e,00,30,00,00,00,32,00,35,00,35,00,2e,00,32,00,35,00,35,00,2e,00,\
32,00,35,00,35,00,2e,00,30,00,00,00,32,00,35,00,35,00,2e,00,32,00,35,00,35,\
00,2e,00,32,00,35,00,35,00,2e,00,30,00,00,00,32,00,35,00,35,00,2e,00,32,00,\
35,00,35,00,2e,00,32,00,35,00,35,00,2e,00,30,00,00,00,32,00,35,00,35,00,2e,\
00,32,00,35,00,35,00,2e,00,32,00,35,00,35,00,2e,00,30,00,00,00,00,00
which is 255.255.255.0 255.255.255.0 255.255.255.0 255.255.255.0 255.255.255.0
"DefaultGateway"=hex(7):31,00,39,00,32,00,2e,00,31,00,36,00,38,00,2e,00,32,00,\
35,00,34,00,2e,00,32,00,35,00,34,00,00,00,00,00
which is 192.168.254.254
"DefaultGatewayMetric"=hex(7):30,00,00,00,00,00
"NameServer"="192.168.254.254"
"Domain"=""
"RegistrationEnabled"=dword:00000001
"RegisterAdapterName"=dword:00000000
"TCPAllowedPorts"=hex(7):30,00,00,00,00,00
"UDPAllowedPorts"=hex(7):30,00,00,00,00,00
"RawIPAllowedProtocols"=hex(7):30,00,00,00,00,00
"NTEContextList"=hex(7):00,00
"DhcpClassIdBin"=hex:
"DhcpServer"="255.255.255.255"
"Lease"=dword:00000e10
"LeaseObtainedTime"=dword:51185713
"T1"=dword:51185e1b
"T2"=dword:51186361
"LeaseTerminatesTime"=dword:51186523
"IPAutoconfigurationAddress"="0.0.0.0"
"IPAutoconfigurationMask"="255.255.0.0"
"IPAutoconfigurationSeed"=dword:00000000
"AddressType"=dword:00000000
I exclude the Fortigates as part of the problem since just needed to reboot A1.
2013-09-19 : Issue again. Seems to occur everytime the VPNs drops between the Fortigates.
HOCHELAGA_2 # get router info routing-table all
Codes: K - kernel, C - connected, S - static, R - RIP, B - BGP
O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default
S* 0.0.0.0/0 [10/0] via 64.15.130.49, wan1
C 10.10.10.0/24 is directly connected, dmz
C 10.100.254.1/32 is directly connected, fat
C 10.100.254.2/32 is directly connected, fat
C 64.15.130.48/28 is directly connected, wan1
is directly connected, wan1
is directly connected, wan1
is directly connected, wan1
is directly connected, wan1
is directly connected, wan1
S 192.168.200.0/24 [10/0] via 10.100.254.2, fat
C 192.168.250.0/24 is directly connected, internal
S 192.168.252.0/24 [10/0] is directly connected, hoch st-bruno
S 192.168.253.0/24 [10/0] is directly connected, HOCH-KAN
C 192.168.254.0/24 is directly connected, internal
is directly connected, internal
is directly connected, internal
HOCHELAGA_2 # diagnose ip route list
tab=254 vf=0 scope=253 type=1 proto=2 prio=0 0.0.0.0/0.0.0.0/0->10.100.254.2/32 pref=10.100.254.1 gwy=0.0.0.0 dev=11(fat)
tab=254 vf=0 scope=253 type=1 proto=2 prio=0 0.0.0.0/0.0.0.0/0->64.15.130.48/28 pref=64.15.130.56 gwy=0.0.0.0 dev=3(wan1)
tab=254 vf=0 scope=253 type=1 proto=2 prio=0 0.0.0.0/0.0.0.0/0->169.254.0.64/26 pref=169.254.0.66 gwy=0.0.0.0 dev=16(havdlink1)
tab=254 vf=0 scope=0 type=1 proto=11 prio=0 0.0.0.0/0.0.0.0/0->192.168.200.0/24 pref=0.0.0.0 gwy=10.100.254.2 dev=11(fat)
tab=254 vf=0 scope=253 type=1 proto=2 prio=0 0.0.0.0/0.0.0.0/0->192.168.250.0/24 pref=192.168.250.254 gwy=0.0.0.0 dev=5(internal)
tab=254 vf=0 scope=253 type=1 proto=2 prio=0 0.0.0.0/0.0.0.0/0->10.10.10.0/24 pref=10.10.10.1 gwy=0.0.0.0 dev=4(dmz)
tab=254 vf=0 scope=0 type=1 proto=11 prio=0 0.0.0.0/0.0.0.0/0->192.168.252.0/24 pref=0.0.0.0 gwy=0.0.0.0 dev=9(hoch st-bruno)
tab=254 vf=0 scope=0 type=1 proto=11 prio=0 0.0.0.0/0.0.0.0/0->192.168.253.0/24 pref=0.0.0.0 gwy=0.0.0.0 dev=10(HOCH-KAN)
tab=254 vf=0 scope=253 type=1 proto=2 prio=0 0.0.0.0/0.0.0.0/0->192.168.254.0/24 pref=192.168.254.254 gwy=0.0.0.0 dev=5(internal)
tab=254 vf=0 scope=0 type=1 proto=11 prio=0 0.0.0.0/0.0.0.0/0->0.0.0.0/0 pref=0.0.0.0 gwy=64.15.130.49 dev=3(wan1)
tab=255 vf=0 scope=253 type=3 proto=2 prio=0 0.0.0.0/0.0.0.0/0->64.15.130.63/32 pref=64.15.130.56 gwy=0.0.0.0 dev=3(wan1)
tab=255 vf=0 scope=253 type=3 proto=2 prio=0 0.0.0.0/0.0.0.0/0->127.255.255.255/32 pref=127.0.0.1 gwy=0.0.0.0 dev=7(root)
tab=255 vf=0 scope=254 type=2 proto=2 prio=0 0.0.0.0/0.0.0.0/0->10.10.10.1/32 pref=10.10.10.1 gwy=0.0.0.0 dev=4(dmz)
tab=255 vf=0 scope=253 type=3 proto=2 prio=0 0.0.0.0/0.0.0.0/0->10.10.10.0/32 pref=10.10.10.1 gwy=0.0.0.0 dev=4(dmz)
tab=255 vf=0 scope=254 type=2 proto=2 prio=0 0.0.0.0/0.0.0.0/0->10.100.254.1/32 pref=10.100.254.1 gwy=0.0.0.0 dev=11(fat)
tab=255 vf=0 scope=254 type=2 proto=2 prio=0 0.0.0.0/0.0.0.0/0->64.15.130.59/32 pref=64.15.130.59 gwy=0.0.0.0 dev=2(wan2)
tab=255 vf=0 scope=254 type=2 proto=2 prio=0 0.0.0.0/0.0.0.0/0->192.168.254.2/32 pref=192.168.254.254 gwy=0.0.0.0 dev=5(internal)
tab=255 vf=0 scope=254 type=2 proto=2 prio=0 0.0.0.0/0.0.0.0/0->64.15.130.58/32 pref=64.15.130.56 gwy=0.0.0.0 dev=3(wan1)
tab=255 vf=0 scope=254 type=2 proto=2 prio=0 0.0.0.0/0.0.0.0/0->169.254.0.66/32 pref=169.254.0.66 gwy=0.0.0.0 dev=16(havdlink1)
tab=255 vf=0 scope=253 type=3 proto=2 prio=0 0.0.0.0/0.0.0.0/0->192.168.250.0/32 pref=192.168.250.254 gwy=0.0.0.0 dev=5(internal)
tab=255 vf=0 scope=254 type=2 proto=2 prio=0 0.0.0.0/0.0.0.0/0->192.168.254.1/32 pref=192.168.254.254 gwy=0.0.0.0 dev=5(internal)
tab=255 vf=0 scope=254 type=2 proto=2 prio=0 0.0.0.0/0.0.0.0/0->64.15.130.57/32 pref=64.15.130.56 gwy=0.0.0.0 dev=3(wan1)
tab=255 vf=0 scope=253 type=3 proto=2 prio=0 0.0.0.0/0.0.0.0/0->192.168.254.0/32 pref=192.168.254.254 gwy=0.0.0.0 dev=5(internal)
tab=255 vf=0 scope=254 type=2 proto=2 prio=0 0.0.0.0/0.0.0.0/0->64.15.130.56/32 pref=64.15.130.56 gwy=0.0.0.0 dev=3(wan1)
tab=255 vf=0 scope=253 type=3 proto=2 prio=0 0.0.0.0/0.0.0.0/0->169.254.0.64/32 pref=169.254.0.66 gwy=0.0.0.0 dev=16(havdlink1)
tab=255 vf=0 scope=254 type=2 proto=2 prio=0 0.0.0.0/0.0.0.0/0->64.15.130.54/32 pref=64.15.130.56 gwy=0.0.0.0 dev=3(wan1)
tab=255 vf=0 scope=253 type=3 proto=2 prio=0 0.0.0.0/0.0.0.0/0->169.254.0.127/32 pref=169.254.0.66 gwy=0.0.0.0 dev=16(havdlink1)
tab=255 vf=0 scope=254 type=2 proto=2 prio=0 0.0.0.0/0.0.0.0/0->64.15.130.53/32 pref=64.15.130.56 gwy=0.0.0.0 dev=3(wan1)
tab=255 vf=0 scope=254 type=2 proto=2 prio=0 0.0.0.0/0.0.0.0/0->64.15.130.52/32 pref=64.15.130.56 gwy=0.0.0.0 dev=3(wan1)
tab=255 vf=0 scope=253 type=3 proto=2 prio=0 0.0.0.0/0.0.0.0/0->10.10.10.255/32 pref=10.10.10.1 gwy=0.0.0.0 dev=4(dmz)
tab=255 vf=0 scope=253 type=3 proto=2 prio=0 0.0.0.0/0.0.0.0/0->127.0.0.0/32 pref=127.0.0.1 gwy=0.0.0.0 dev=7(root)
tab=255 vf=0 scope=254 type=2 proto=2 prio=0 0.0.0.0/0.0.0.0/0->192.168.254.254/32 pref=192.168.254.254 gwy=0.0.0.0 dev=5(internal)
tab=255 vf=0 scope=253 type=3 proto=2 prio=0 0.0.0.0/0.0.0.0/0->192.168.250.255/32 pref=192.168.250.254 gwy=0.0.0.0 dev=5(internal)
tab=255 vf=0 scope=254 type=2 proto=2 prio=0 0.0.0.0/0.0.0.0/0->127.0.0.1/32 pref=127.0.0.1 gwy=0.0.0.0 dev=7(root)
tab=255 vf=0 scope=253 type=3 proto=2 prio=0 0.0.0.0/0.0.0.0/0->64.15.130.48/32 pref=64.15.130.56 gwy=0.0.0.0 dev=3(wan1)
tab=255 vf=0 scope=254 type=2 proto=2 prio=0 0.0.0.0/0.0.0.0/0->192.168.250.254/32 pref=192.168.250.254 gwy=0.0.0.0 dev=5(internal)
tab=255 vf=0 scope=253 type=3 proto=2 prio=0 0.0.0.0/0.0.0.0/0->192.168.254.255/32 pref=192.168.254.254 gwy=0.0.0.0 dev=5(internal)
tab=255 vf=0 scope=254 type=2 proto=2 prio=0 0.0.0.0/0.0.0.0/0->127.0.0.0/8 pref=127.0.0.1 gwy=0.0.0.0 dev=7(root)
PING succesfull on a server
diagnose sniffer packet any "host 192.168.253.23" 4
23.232067 internal in 192.168.254.15 -> 192.168.253.23: icmp: echo request
23.232329 HOCH-KAN out 192.168.254.15 -> 192.168.253.23: icmp: echo request
23.248800 HOCH-KAN in 192.168.253.23 -> 192.168.254.15: icmp: echo reply
23.248932 internal out 192.168.253.23 -> 192.168.254.15: icmp: echo reply
PING failed on a server
diagnose sniffer packet any "host 192.168.253.18" 4
8.212249 internal in 192.168.254.15 -> 192.168.253.18: icmp: echo request
8.212479 wan1 out 64.15.130.56 -> 192.168.253.18: icmp: echo request
10.508155 internal in 192.168.254.15.1113 -> 192.168.253.18.139: syn 1271941747
10.508436 wan1 out 64.15.130.56.42334 -> 192.168.253.18.139: syn 1271941747
11.706287 internal in 192.168.254.15.1112 -> 192.168.253.18.445: syn 341420858
11.706540 wan1 out 64.15.130.56.42332 -> 192.168.253.18.445: syn 341420858
Why the route taken is different for the server on the same network ? I don't use any RIP, OSPF, BGP routing. No policy routing. Juste a static route between VPNs. Nothing is showing a dynamic route for 192.168.253.23 and the Fortigate decide to route it into the wan1 interface instead.
Anything I could check next time it happens ?
Thank in advance
And sorry if is not fully clear, french is my mother language
S.
Best Answer
We finally found the reason. It is related to Fortigate ICMP session timeout problem. When VPN is down, ICMP session is marked to go via interface directly rather than VPN tunnel. However, when VPN recovers, the session via path is not modified until live time becomes zero. If you keep pinging, the live time can never be zero.