Okay, defer is now enabled on pfsync interface (sorry for my last idea,
i haven't the man on me :) ).
It seems the problem isn't resolved.
The transfer starts but blocked at random time.
-- 
Best regards, 

Loïc BLOT, Engineering
UNIX Systems, Security and Networks
http://www.unix-experience.fr


Le mercredi 03 juillet 2013 à 08:12 +0200, Loïc BLOT a écrit :
> Hi,
> Thanks for your reply. I wasn't careful about this section.
> If i understand i must add defer option to my WAN iface (or i'm wrong i
> must add it to my vlan995 iface ?) ?
> 
> I will test it this morning, and i return back to misc :)
> --
> Best regards,
> Loc BLOT,
> UNIX systems, security and network expert
> http://www.unix-experience.fr
> 
> 
> Le mercredi 03 juillet 2013  02:02 +0200, mxb a crit :
> > pfsync(4) explains this:
> >
> > " The pfsync interface will attempt to collapse multiple state updates
> into
> >      a single packet where possible.  The maximum number of times a single
> >      state can be updated before a pfsync packet will be sent out is
> >      controlled by the maxupd parameter
> > "
> >
> >
> > and
> >
> > " Where more than one firewall might actively handle packets, e.g. with
> >      certain ospfd(8), bgpd(8) or carp(4) configurations, it is beneficial
> to
> >      defer transmission of the initial packet of a connection.  The pfsync
> >      state insert message is sent immediately; the packet is queued until
> >      either this message is acknowledged by another system, or a timeout
> has
> >      expired.  This behaviour is enabled with the defer parameter to
> >      ifconfig(8).
> > "
> >
> >
> > Eg. "defer: on", yours is "off".
> >
> > //mxb
> >
> >
> > On 2 jul 2013, at 21:54, Loc BLOT <loic.b...@unix-experience.fr> wrote:
> >
> > > Hi all
> > > I have a strange issue (or i haven't read pfsync correctly but i don't
> > > think this is the problem :D)
> > >
> > > I'm using 2 OpenBSD as BGP+OSPF routers at the border of one site.
> > >
> > > Those BGP routers are secure with strong PF in stateful mode, and the
> > > stateful is working very well on each router. Because of my full mesh
> > > BGP configuration, the outgoing layer 7 sessions can leave my network by
> > > one router and responses can income by the other.
> > >
> > > To resolve this issue, i have created a dedidated VLAN for the pfsync
> > > traffic and attached pfsync to this VLAN.
> > >
> > > Here is a sample output of ifconfig on my first router:
> > >
> > > vlan995: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
> > >        lladdr a0:36:9f:10:4a:a6
> > >        priority: 0
> > >        vlan: 995 parent interface: trunk1
> > >        groups: vlan
> > >        status: active
> > >        inet6 fe80::a236:9fff:fe10:4aa6%vlan995 prefixlen 64 scopeid
> > > 0x10
> > >        inet 10.117.1.129 netmask 0xfffffff8 broadcast 10.117.1.135
> > > pfsync0: flags=41<UP,RUNNING> mtu 1500
> > >        priority: 0
> > >        pfsync: syncdev: vlan995 maxupd: 255 defer: off
> > >        groups: carp pfsync
> > >
> > > And here on my second router:
> > >
> > > vlan995: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
> > >        lladdr a0:36:9f:17:e2:1e
> > >        priority: 0
> > >        vlan: 995 parent interface: trunk1
> > >        groups: vlan
> > >        status: active
> > >        inet6 fe80::a236:9fff:fe17:e21e%vlan995 prefixlen 64 scopeid
> > > 0x10
> > >        inet 10.117.1.130 netmask 0xfffffff8 broadcast 10.117.1.135
> > > pfsync0: flags=41<UP,RUNNING> mtu 1500
> > >        priority: 0
> > >        pfsync: syncdev: vlan995 maxupd: 255 defer: off
> > >        groups: carp pfsync
> > >
> > > As you see in next tcpdump capture, there is some discussions between
> > > the two routers:
> > >
> > > # tcpdump -nni vlan995
> > > tcpdump: listening on vlan995, link-type EN10MB
> > > tcpdump: WARNING: compensating for unaligned libpcap packets
> > > 23:41:13.699617 10.117.1.130: PFSYNCv6 len 108
> > >    act UPD ST COMP count 1
> > >    ...
> > > (DF) [tos 0x10]
> > > 23:41:14.158500 10.117.1.129: PFSYNCv6 len 108
> > >    act UPD ST COMP count 1
> > >    ...
> > > (DF) [tos 0x10]
> > > 23:41:14.941396 SSTP STP config root=83e3.0:a:b8:7b:27:80 rootcost=3
> > > bridge=c3e3.0:17:e:2e:f:80 port=142 ifcost=130 age=1/0 max=20/0
> > > hello=2/0 fwdelay=15/0 pvid=995
> > > 23:41:14.949617 10.117.1.130: PFSYNCv6 len 108
> > >    act UPD ST COMP count 1
> > >    ...
> > > (DF) [tos 0x10]
> > > 23:41:15.237655 10.117.1.129: PFSYNCv6 len 640
> > >    act UPD ST COMP count 1
> > >    ...
> > > (DF) [tos 0x10]
> > > 23:41:15.949617 10.117.1.130: PFSYNCv6 len 124
> > >    act UPD ST COMP count 1
> > >    ...
> > > (DF) [tos 0x10]
> > > 23:41:16.255230 10.117.1.129: PFSYNCv6 len 36
> > >    act DEL ST COMP count 1
> > >        id: 51d16a3500006c33 creatorid: a10bbd21
> > > (DF) [tos 0x10]
> > > 23:41:16.946454 SSTP STP config root=83e3.0:a:b8:7b:27:80 rootcost=3
> > > bridge=c3e3.0:17:e:2e:f:80 port=142 ifcost=130 age=1/0 max=20/0
> > > hello=2/0 fwdelay=15/0 pvid=995
> > > 23:41:16.949619 10.117.1.130: PFSYNCv6 len 1116
> > >    act UPD ST COMP count 13
> > >    ...
> > > (DF) [tos 0x10]
> > >
> > >
> > > The problem is simple, when i initiate a stateful connection from one
> > > server, the return (by second router) is blocked by PF (i see the return
> > > with pflog0)
> > >
> > > To be precise here is an example (and tested path):
> > >
> > > OBSD NTP -> OBSD router 1 -> WAN...ftp.fr.openbsd.org...WAN -> OBSD
> > > router 2 || blocked
> > >
> > > PF allow in/out routing traffic from this server but incoming from WAN
> > > is blocked by default
> > >
> > > Can you confirm to me that pfsync may add a state for outgoing tcp
> > > connection in the second router when the first router add it ?
> > > Have you got any idea on this issue ?
> > >
> > > --
> > > Best regards,
> > > Loc BLOT,
> > > UNIX systems, security and network expert
> > > http://www.unix-experience.fr
> > >
> > > [demime 1.01d removed an attachment of type application/pgp-signature
> which had a name of signature.asc]
> 
> [demime 1.01d removed an attachment of type application/pgp-signature which 
> had a name of signature.asc]

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