This is mostly confusing that the packets are not seen on the VR public
interface, seeing as other services are working.
If it was a local NAT issue then the packet would atleast get into that
interface. Do you have any upstream devices providing NAT? Or any other VR
with the issue?

It may be worth recreating the VR, by stopping and destroying it and
creating another guest to start a fresh.

Marty


On Sun, Sep 15, 2013 at 8:12 PM, Noel Kendall <[email protected]>wrote:

> Marty, if I run a telnet <www.xyz.com> 80 from a shell in the guest,
> while running a tcpdumpon the public i/f of the VR:
> - I can see the outbound packets going out- I do not see a response packet
> coming back in
> FYI there are no firewalls outbound from the KVM host. The host bridges vi
> CS networkingdirectly out on to the internet via a switch.
> Note that traffic from outside (ssh, web) can happily traverse the VR to
> the guest. I get the usualits working html page from the guest. This tells
> me that there is nothing outbound from the VR thatis filtering packets.
> Am truly stumped. This is mysterious indeed.
> From within the VR, can happily telnet to <www.xyz.com> 80 and receive
> response.Only if packet came from guest and was forwarded does the response
> not show up.
> In short:
> wget from VR to www.xyz.com works, response received and saved
> wget from guest to www.xyz.com does not work, network not available
> displayed on guest, response packets not seen on the public i/f of VR at all
> Noel
>
> > Date: Sun, 15 Sep 2013 18:16:17 +0100
> > Subject: Re: Advanced Network - SNAT not working
> > From: [email protected]
> > To: [email protected]
> >
> > Hi Noel,
> >
> > Can you answer: Does the traffic come back on the public interface? and
> > then onto the Guest interface?
> >
> > Thanks,
> > Marty
> >
> >
> > On Sun, Sep 15, 2013 at 2:05 PM, Noel Kendall <[email protected]
> >wrote:
> >
> > > Indeed, yes, a wget executed on the VR to a public website works just
> fine.
> > > Noel
> > >
> > > > Date: Sun, 15 Sep 2013 13:15:20 +0100
> > > > Subject: Re: Advanced Network - SNAT not working
> > > > From: [email protected]
> > > > To: [email protected]
> > > >
> > > > Hi Noel,
> > > >
> > > > Does the traffic come back on the public interface? and then onto the
> > > Guest
> > > > interface?
> > > >
> > > > Does a wget on the VR work?
> > > >
> > > > Marty
> > > >
> > > >
> > > > On Sat, Sep 14, 2013 at 8:19 PM, Noel Kendall <
> [email protected]
> > > >wrote:
> > > >
> > > > > I have that Marty. I see the http outbound request coming in on the
> > > guest
> > > > > interface of the VR,and see the http request being sent out on the
> > > public
> > > > > interface of the VR.
> > > > > The traffic is flowing fine from guest to the outbound i/f of the
> VR.
> > > > > This is tcpdump on the public i/f while guest is doing wget to
> > > > > 6x.xxx.xxx.xxx
> > > > >
> > > > > 19:17:58.834932 06:e3:3a:00:01:0a > 00:0c:86:4e:fe:00, ethertype
> IPv4
> > > > > (0x0800), length 74: 10.11.79.178.39074 > 6x.xxx.xxx.xx.80: Flags
> [S],
> > > seq
> > > > > 1859313238, win 14600, options [mss 1460,sackOK,TS val 27489348 ecr
> > > > > 0,nop,wscale 4], length 0  0x0000:  4500 003c ad1d 4000 3f06 2d13
> 0a0b
> > > 4fb2
> > > > >        0x0010:  416e c660 98a2 0050 6ed2 de56 0000 0000
>  0x0020:
> > > > >  a002 3908 516c 0000 0204 05b4 0402 080a        0x0030:  01a3 7444
> 0000
> > > > > 0000 0103 0304
> > > > >
> > > > >
> > > > > > Date: Sat, 14 Sep 2013 19:29:53 +0100
> > > > > > Subject: Re: Advanced Network - SNAT not working
> > > > > > From: [email protected]
> > > > > > To: [email protected]
> > > > > >
> > > > > > Hi Noel,
> > > > > >
> > > > > > Can you run a tcpdump on both VR interfaces, this should make it
> > > apparent
> > > > > > what is happening?
> > > > > >
> > > > > > Thanks,
> > > > > > Marty
> > > > > >
> > > > > >
> > > > > > On Sat, Sep 14, 2013 at 6:41 PM, Noel Kendall <
> > > [email protected]
> > > > > >wrote:
> > > > > >
> > > > > > > http://pastebin.com/3FZmFnvZ
> > > > > > > Many thanks Marty.
> > > > > > > Noel
> > > > > > > > Date: Sat, 14 Sep 2013 18:07:55 +0100
> > > > > > > > Subject: Re: Advanced Network - SNAT not working
> > > > > > > > From: [email protected]
> > > > > > > > To: [email protected]
> > > > > > > >
> > > > > > > > Hi Noel,
> > > > > > > >
> > > > > > > > Could you put the IP tables on pastebin? GMail has collapsed
> the
> > > > > lines
> > > > > > > > horrifically.
> > > > > > > > Have you also tried a tcpdump on both interfaces on the VR?
> > > > > > > > tcpdump -i eth0 <--- Or whatever it may be called
> > > > > > > >
> > > > > > > > I would expect worse connectivity if it was a pure NAT issue,
> > > but I
> > > > > will
> > > > > > > > review the tables later.
> > > > > > > >
> > > > > > > > Thanks,
> > > > > > > > Marty
> > > > > > > >
> > > > > > > >
> > > > > > > > On Sat, Sep 14, 2013 at 5:55 PM, Noel Kendall <
> > > > > [email protected]
> > > > > > > >wrote:
> > > > > > > >
> > > > > > > > > Not seeing return packets on VR. Suspect, therefore, that
> SNAT
> > > is
> > > > > > > fouled
> > > > > > > > > up in some way.I have been doing wget to from guest, can
> see
> > > the
> > > > > > > outgoing
> > > > > > > > > request fine, both in the guest andthe VR.
> > > > > > > > > Could it be that the SNAT table entries from the
> > > 10.11.0.0/16subnet
> > > > > > > to
> > > > > > > > > dpt www are interfering withthe SNAT to public ip?? (wild
> > > guess) -
> > > > > not
> > > > > > > an
> > > > > > > > > iptables expert by any stretch of the imagination
> > > > > > > > > 67.xxx.xxx.56 is the guest public IP10.11.79.178 is the
> guest
> > > IP on
> > > > > > > guest
> > > > > > > > > network
> > > > > > > > > iptables _L -t nat on the VR shows...
> > > > > > > > > Chain PREROUTING (policy ACCEPT)target     prot opt source
> > > > > > > > > destination         DNAT       tcp  --  anywhere
> > > > > anywhere
> > > > > > > > >      tcp dpt:domain to:10.11.0.1 DNAT       tcp  --
>  anywhere
> > > > > > > > > 67.xxx.xxx.56        tcp dpt:www to:10.11.79.178:80 DNAT
> > > > > tcp  --
> > > > > > > > >  anywhere             67.xxx.xxx.56        tcp dpt:www
> > > > > > > to:10.11.79.178:80DNAT       tcp  --  anywhere
> > > > > 67.xxx.xxx.56
> > > > > > >        tcp dpt:https
> > > > > > > > > to:10.11.79.178:443 DNAT       tcp  --  anywhere
> > > > > > > > > 67.xxx.xxx.56        tcp dpt:https to:10.11.79.178:443DNAT
> > > > > tcp
> > > > > > >  --
> > > > > > > > >  anywhere             67.xxx.xxx.56        tcp dpt:ssh
> > > > > > > to:10.11.79.178:22DNAT       tcp  --  anywhere
> > > > > 67.xxx.xxx.56
> > > > > > >        tcp dpt:ssh
> > > > > > > > > to:10.11.79.178:22 DNAT       tcp  --  anywhere
> > > > > > > 67.xxx.xxx.56
> > > > > > > > >        tcp dpt:ftp to:10.11.79.178:21 DNAT       tcp  --
> > >  anywhere
> > > > > > > > >       67.xxx.xxx.56        tcp dpt:ftp to:10.11.79.178:21DNAT
> > > > > > > tcp
> > > > > > > > >  --  anywhere             67.xxx.xxx.56        tcp
> dpt:5901 to:
> > > > > > > > > 10.11.79.178:5901 DNAT       tcp  --  anywhere
> > > > > > > 67.xxx.xxx.56
> > > > > > > > >        tcp dpt:5901 to:10.11.79.178:5901
> > > > > > > > > Chain POSTROUTING (policy ACCEPT)target     prot opt source
> > > > > > > > > destination         SNAT       all  --  anywhere
> > > > > anywhere
> > > > > > > > >      to:67.xxx.xxx.56  SNAT       all  --  anywhere
> > > > > > > anywhere
> > > > > > > > >          to:67.xxx.xxx.56  SNAT       all  --  anywhere
> > > > > > > > > anywhere            to:67.xxx.xxx.56 SNAT       all  --
> > >  anywhere
> > > > > > > > >   anywhere            to:67.xxx.xxx.56 SNAT       all  --
> > >  anywhere
> > > > > > > > >     anywhere            to:67.xxx.xxx.56SNAT       all  --
> > > > >  anywhere
> > > > > > > > >       anywhere            to:67.xxx.xxx.56 SNAT       all
>  --
> > > > >  anywhere
> > > > > > > > >         anywhere            to:67.xxx.xxx.56 SNAT
> all  --
> > > > > > >  anywhere
> > > > > > > > >           anywhere            to:67.xxx.xxx.56 SNAT
> tcp
> > >  --
> > > > > > > > > 10.11.0.0/16         myguest             tcp dpt:www
> > > to:10.11.0.1
> > > > > SNAT
> > > > > > > > >     tcp  --  10.11.0.0/16         myguest             tcp
> > > > > dpt:https
> > > > > > > > > to:10.11.0.1 SNAT       tcp  --  10.11.0.0/16
> myguest
> > > > > > > > > tcp dpt:ssh to:10.11.0.1 SNAT       tcp  --  10.11.0.0/16
> > > > > > > myguest
> > > > > > > > >             tcp dpt:ftp to:10.11.0.1 SNAT       tcp  --
> > > > > 10.11.0.0/16
> > > > > > > > >     myguest             tcp dpt:5901 to:10.11.0.1 SNAT
> > > all
> > > > >  --
> > > > > > > > >  anywhere             anywhere            to:67.xxx.xxx.56
> > > > > > > > > Chain OUTPUT (policy ACCEPT)target     prot opt source
> > > > > > > > > destination         DNAT       tcp  --  anywhere
> > > > > > > 67.xxx.xxx.56
> > > > > > > > >       tcp dpt:www to:10.11.79.178:80 DNAT       tcp  --
> > >  anywhere
> > > > > > > > >     67.xxx.xxx.56       tcp dpt:https to:10.11.79.178:443DNAT
> > > > > > > tcp
> > > > > > > > >  --  anywhere             67.xxx.xxx.56       tcp dpt:ssh
> to:
> > > > > > > > > 10.11.79.178:22 DNAT       tcp  --  anywhere
> > > > > 67.xxx.xxx.56
> > > > > > > > >     tcp dpt:ftp to:10.11.79.178:21 DNAT       tcp  --
> > >  anywhere
> > > > > > > > >   67.xxx.xxx.56       tcp dpt:5901 to:10.11.79.178:5901
> > > > > > > > >
> > > > > > > > > > Date: Sat, 14 Sep 2013 17:25:14 +0100
> > > > > > > > > > Subject: Re: Advanced Network - SNAT not working
> > > > > > > > > > From: [email protected]
> > > > > > > > > > To: [email protected]
> > > > > > > > > >
> > > > > > > > > > Hi Noel,
> > > > > > > > > >
> > > > > > > > > > Can you try using telnet to connect to an external
> webserver?
> > > > > telnet
> > > > > > > > > > www.google.com 80
> > > > > > > > > > Can you also clarify: do you see the response packets
> reach
> > > the
> > > > > VR
> > > > > > > and/or
> > > > > > > > > > on what interfaces?
> > > > > > > > > >
> > > > > > > > > > Thanks,
> > > > > > > > > > Marty
> > > > > > > > > >
> > > > > > > > > > On Saturday, September 14, 2013, Noel Kendall wrote:
> > > > > > > > > >
> > > > > > > > > > > Guest OS cannot receive responses to http GETs from
> > > resources
> > > > > on
> > > > > > > the
> > > > > > > > > > > Internet.
> > > > > > > > > > > Network is advanced, VLAN isolated.
> > > > > > > > > > > What is working:
> > > > > > > > > > > - can browse guest website from internet- can ssh to
> guest
> > > from
> > > > > > > > > internet-
> > > > > > > > > > > can VPN to guest network from internet
> > > > > > > > > > > - network VR can access internet sites no problem
> > > > > > > > > > > What is not working:
> > > > > > > > > > > - guest http traffic to external website gets to VR on
> > > internal
> > > > > > > NIC,
> > > > > > > > > > > packets forwarded to external site via external NIC
> > > > > > > > > > >
> > > > > > > > > > > Response traffic is not seen. Appears to be dropped.
> > > > > > > > > > > Have been looking hard at IPTABLES rules, doing
> tcpdumps,
> > > etc.
> > > > > > > > > > > Am at this point stumped.
> > > > > > > > > > > Any ideas on what could be wrong, or how to determine
> what
> > > > > could be
> > > > > > > > > wrong?
> > > > > > > > > > > Thanks in advance everyone who tries to help!
> > > > > > > > > > > N.
> > > > > > > > > > >
> > > > > > > > >
> > > > > > > > >
> > > > > > >
> > > > > > >
> > > > >
> > > > >
> > >
> > >
>
>

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