In the failing scenario where a host in vlan 1 with IP addr. 10.215.111.210 cannot ping a host in vlan 18 with IP addr. 10.215.144.251 this is what I see on the SW FW:
# tcpdump -n -i lan -e vlan and host 10.215.144.251 dropped privs to pcap tcpdump: verbose output suppressed, use -v[v]... for full protocol decode listening on lan, link-type EN10MB (Ethernet), snapshot length 262144 bytes 00:01:27.495068 9c:7b:ef:b7:7a:a1 > b8:59:9f:cc:bb:5c, ethertype 802.1Q (0x8100), length 78: vlan 1, p 0, ethertype IPv4 (0x0800), 10.215.111.210 > 10.215.144.251: ICMP echo request, id 1, seq 3845, length 40 00:01:27.495095 b8:59:9f:cc:bb:5c > 94:40:c9:26:dc:80, ethertype 802.1Q (0x8100), length 78: vlan 18, p 0, ethertype IPv4 (0x0800), 10.215.111.210 > 10.215.144.251: ICMP echo request, id 1, seq 3845, length 40 00:01:27.495105 9c:7b:ef:b7:7a:a1 > ff:ff:ff:ff:ff:ff, ethertype 802.1Q (0x8100), length 78: vlan 50, p 0, ethertype IPv4 (0x0800), 10.215.111.210 > 10.215.144.251: ICMP echo request, id 1, seq 3845, length 40 00:01:27.495293 94:40:c9:26:dc:80 > ac:1f:6b:f5:b7:1b, ethertype 802.1Q (0x8100), length 78: vlan 18, p 0, ethertype IPv4 (0x0800), 10.215.144.251 > 10.215.111.210: ICMP echo reply, id 1, seq 3845, length 40 # ip a s lan.18 65: lan.18@lan: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000 link/ether b8:59:9f:cc:bb:5c brd ff:ff:ff:ff:ff:ff inet 192.168.240.1/24 brd 192.168.240.255 scope global lan.18 valid_lft forever preferred_lft forever # ip a s ext 139: ext: <BROADCAST,MULTICAST,MASTER,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000 link/ether ac:1f:6b:f5:b7:1b brd ff:ff:ff:ff:ff:ff inet 192.168.170.1/24 brd 192.168.170.255 scope global ext valid_lft forever preferred_lft forever # ip neigh list | grep 10.215.144.251 10.215.144.251 dev lan.18 lladdr 94:40:c9:26:dc:80 REACHABLE Ignore vlan 50 as it's just for port mirroring traffic to an IDS. So to sum it up: - host with IP addr. 10.215.111.210 and MAC addr. 9c:7b:ef:b7:7a:a1 sends a ping request which hits the FW's lan.18 interface with MAC addr. b8:59:9f:cc:bb:5c - the ICMP request is sent out to the MAC addr. 94:40:c9:26:dc:80 which is that of the DST host with IP addr. 10.215.144.251 - the ICMP reply comes back on the FW's vlan 18 interface and is sent to 10.215.111.210 (SRC addr.) through MAC addr. ac:1f:6b:f5:b7:1b - However, interface "ext" has nothing to do with vlan 1 so why are the reply packets sent there? On the other hand, in the successful scenario where a host in vlan 1 with IP addr. 10.215.111.210 can ping a host in vlan 18 with IP addr. 10.215.144.129 this is what I see on the SW FW: # tcpdump -n -i lan -e vlan and host 10.215.144.129 dropped privs to pcap tcpdump: verbose output suppressed, use -v[v]... for full protocol decode listening on lan, link-type EN10MB (Ethernet), snapshot length 262144 bytes 00:16:18.875974 9c:7b:ef:b7:7a:a1 > b8:59:9f:cc:bb:5c, ethertype 802.1Q (0x8100), length 78: vlan 1, p 0, ethertype IPv4 (0x0800), 10.215.111.210 > 10.215.144.129: ICMP echo request, id 1, seq 4050, length 40 00:16:18.875992 b8:59:9f:cc:bb:5c > 94:40:c9:26:e2:d2, ethertype 802.1Q (0x8100), length 78: vlan 18, p 0, ethertype IPv4 (0x0800), 10.215.111.210 > 10.215.144.129: ICMP echo request, id 1, seq 4050, length 40 00:16:18.876005 9c:7b:ef:b7:7a:a1 > ff:ff:ff:ff:ff:ff, ethertype 802.1Q (0x8100), length 78: vlan 50, p 0, ethertype IPv4 (0x0800), 10.215.111.210 > 10.215.144.129: ICMP echo request, id 1, seq 4050, length 40 00:16:18.876104 94:40:c9:26:e2:d2 > b8:59:9f:cc:bb:5c, ethertype 802.1Q (0x8100), length 78: vlan 18, p 0, ethertype IPv4 (0x0800), 10.215.144.129 > 10.215.111.210: ICMP echo reply, id 1, seq 4050, length 40 00:16:18.876115 b8:59:9f:cc:bb:5c > 9c:7b:ef:b7:7a:a1, ethertype 802.1Q (0x8100), length 78: vlan 1, p 0, ethertype IPv4 (0x0800), 10.215.144.129 > 10.215.111.210: ICMP echo reply, id 1, seq 4050, length 40 00:16:18.876133 b8:59:9f:cc:bb:5c > ff:ff:ff:ff:ff:ff, ethertype 802.1Q (0x8100), length 78: vlan 50, p 0, ethertype IPv4 (0x0800), 10.215.144.129 > 10.215.111.210: ICMP echo reply, id 1, seq 4050, length 40 # ip neigh list | grep 10.215.144.129 10.215.144.129 dev lan.18 lladdr 94:40:c9:26:e2:d2 REACHABLE Any ideas as to why I'm seeing this? Why is interface "ext" receiving the ICMP replies in the first case? _______________________________________________ Shorewall-users mailing list Shorewall-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/shorewall-users