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AndrLars
New Contributor

reverse path check fail drop intervdom

Hi I was wondering if anyone has seen anything like this.

We have a vdom with a intervdom link

On the inside of the vdom2 we have a VLAN interface 

 

edit "I_VLAN2171"
set vdom "VDOM2"
set ip 10.0.54.1 255.255.255.0
set allowaccess ping
set snmp-index 42
set interface "LACP_INSIDE"
set vlanid 2171

We have routing to that interface apparently since it's directly connected 

 

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] is directly connected, VInkVDOM20
C 10.0.54.0/24 is directly connected, I_VLAN2171
C 10.10.10.0/24 is directly connected, I_VLAN4000
C 185.205.51.40/31 is directly connected, VInkVDOM20
C 185.205.51.40/32 is directly connected, VInkVDOM20

 

The policy to allow traffic out is super easy 

edit 3
set uuid e7de4b72-8ef4-51e7-4882-5ac44d739ced
set srcintf "I_VLAN2171"
set dstintf "VInkVDOM20"
set srcaddr "all"
set dstaddr "all"
set action accept
set schedule "always"
set service "ALL"
set nat enable
next

 

When I in the vdom set 

execute ping-options source 10.0.54.1 and try to ping google dns I get the following.debug trace

 

id=20085 trace_id=101 func=print_pkt_detail line=4903 msg="vd-VDOM2 received a packet(proto=6, 10.0.54.1:20518->10.0.54.2:179) from local. flag [S], seq 2912141760, ack 0, win 14600"
id=20085 trace_id=101 func=init_ip_session_common line=5047 msg="allocate a new session-001445c0"
id=20085 trace_id=102 func=print_pkt_detail line=4903 msg="vd-VDOM2 received a packet(proto=6, 10.0.54.1:20518->10.0.54.2:179) from local. flag [S], seq 2912141760, ack 0, win 14600"
id=20085 trace_id=102 func=resolve_ip_tuple_fast line=4967 msg="Find an existing session, id-001445c0, original direction"
id=20085 trace_id=103 func=print_pkt_detail line=4903 msg="vd-VDOM2 received a packet(proto=6, 10.0.54.1:20518->10.0.54.2:179) from local. flag [S], seq 2912141760, ack 0, win 14600"
id=20085 trace_id=103 func=resolve_ip_tuple_fast line=4967 msg="Find an existing session, id-001445c0, original direction"
id=20085 trace_id=104 func=print_pkt_detail line=4903 msg="vd-VDOM2 received a packet(proto=6, 10.0.54.1:20521->10.0.54.2:179) from local. flag [S], seq 2236177507, ack 0, win 14600"
id=20085 trace_id=104 func=init_ip_session_common line=5047 msg="allocate a new session-001446cb"
id=20085 trace_id=105 func=print_pkt_detail line=4903 msg="vd-VDOM2 received a packet(proto=6, 10.0.54.1:20521->10.0.54.2:179) from local. flag [S], seq 2236177507, ack 0, win 14600"
id=20085 trace_id=105 func=resolve_ip_tuple_fast line=4967 msg="Find an existing session, id-001446cb, original direction"
id=20085 trace_id=106 func=print_pkt_detail line=4903 msg="vd-VDOM2 received a packet(proto=6, 10.0.54.1:20521->10.0.54.2:179) from local. flag [S], seq 2236177507, ack 0, win 14600"
id=20085 trace_id=106 func=resolve_ip_tuple_fast line=4967 msg="Find an existing session, id-001446cb, original direction"
id=20085 trace_id=107 func=print_pkt_detail line=4903 msg="vd-VDOM2 received a packet(proto=1, 10.0.54.1:7936->8.8.8.8:2048) from local. type=8, code=0, id=7936, seq=0."
id=20085 trace_id=107 func=init_ip_session_common line=5047 msg="allocate a new session-001446f6"
id=20085 trace_id=108 func=print_pkt_detail line=4903 msg="vd-root received a packet(proto=1, 10.0.54.1:7936->8.8.8.8:2048) from VInkVDOM21. type=8, code=0, id=7936, seq=0."
id=20085 trace_id=108 func=init_ip_session_common line=5047 msg="allocate a new session-001446f7"
id=20085 trace_id=108 func=ip_route_input_slow line=2247 msg="reverse path check fail, drop"
id=20085 trace_id=108 func=ip_session_handle_no_dst line=5120 msg="trace"

 

This is me now knowing how to configure or a bugg ? 

1 REPLY 1
jwernberg
New Contributor

How is the routing setup in the Root vdom?

"vd-root received a packet(proto=1, 10.0.54.1:7936->8.8.8.8:2048) from VInkVDOM21. type=8, code=0, id=7936, seq=0."

Seems to indicate that the root doesn´t have a route to 10.0.54.0 network on VlinkVdom21 so RPF will drop the packet.

 

Regards Johan

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