[Openvpn-users] openvpn on freebsd: tap

[miml@xxxxxxxxxxxxxxx]

hi

after successfully using openvpn@tun for some week,
it happened me to need bridging.

it seems no howtos exist for freebsd, then i went by
intuition.

enabled bridgind between lan and tap on the bridge
(server) machine; no ip for the server tap interface,
but ip for the client's one.

that's been my try:

remclient                            <->               bridge/server    
                <->         localmachine
(tap0: 192.168.1.35/24)   virt    (mylan0: 192.168.1.100/24)    phys    
 (itslan0: 192.168.1.20/24)


remclient:
tap0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
        inet 192.168.1.35 netmask 0xffffff00 broadcast 192.168.1.255
        inet6 fe80::2bd:5cff:fe27:e900%tap0 prefixlen 64 scopeid 0x8
        ether 00:bd:5c:27:e9:00
        Opened by PID 6173

bridge:
tap0: flags=8943<UP,BROADCAST,RUNNING,PROMISC,SIMPLEX,MULTICAST> mtu 
1500
        inet6 fe80::2bd:42ff:feb6:0%tap0 prefixlen 64 scopeid 0x6
        ether 00:bd:42:b6:00:00
        Opened by PID 649
my0: flags=8943<UP,BROADCAST,RUNNING,PROMISC,SIMPLEX,MULTICAST> mtu 1500
        inet 192.168.1.100 netmask 0xffffff00 broadcast 192.168.1.255
        inet6 fe80::202:44ff:fe0e:d452%my0 prefixlen 64 scopeid 0x2
        ether 00:02:44:0e:d4:52
        media: Ethernet autoselect (100baseTX <full-duplex>)


then, what happens is:

o localmachine does ping remclient's tap0 and mylan0.
o remclient does ping localmachine
o nor localmachine nor the bridge can ping each other:


case 1: remclient tries to ping bridge's lan interface
the bridge receives arp requests from remclient which asks
for bridge's interface. It doesn't answer.

[ tcpdump shows: "date arp who-has *reqip* tell *who'sasking* ]

remclient says:
su-2.05b# tcpdump -ni tap0
tcpdump: listening on tap0
12:23:20.467739 arp who-has 192.168.1.100 tell 192.168.1.35
12:23:21.468246 arp who-has 192.168.1.100 tell 192.168.1.35
...

bridge says:
su-2.05b# tcpdump -ni tap0
tcpdump: WARNING: tap0: no IPv4 address assigned
tcpdump: listening on tap0
12:33:29.888395 arp who-has 192.168.1.100 tell 192.168.1.35
12:33:30.891235 arp who-has 192.168.1.100 tell 192.168.1.35
...


case 2: bridge tries to ping remclient
the bridge now tries to ping remclient. Pings don't succeed, but
the bridge's arpa reqs are correctly answered.

remclient says:
su-2.05b# tcpdump -ni tap0
tcpdump: listening on tap0
12:35:09.672133 arp who-has 192.168.1.35 tell 192.168.1.100
12:35:09.672204 arp reply 192.168.1.35 is-at 0:bd:5c:27:e9:0


bridge says:
su-2.05b# tcpdump -ni tap0
tcpdump: WARNING: tap0: no IPv4 address assigned
tcpdump: listening on tap0
12:34:57.845412 arp who-has 192.168.1.35 tell 192.168.1.100
12:34:57.850775 arp reply 192.168.1.35 is-at 0:bd:5c:27:e9:0
...


then, it seems remclient correctly answer to arps, but bridge
does not for its local physical network interface.
I didn't tried by myself, but people who had my same problems
said it works instead with vtund.
Vtund is completely unuseful to me since it doesn't support win.

if someone has any kind of advice, it'll be very appreciated.

bye


____________________________________________
Openvpn-users mailing list
Openvpn-users@xxxxxxxxxxxxxxxxxxxxx
https://lists.sourceforge.net/lists/listinfo/openvpn-users