perfSONAR User Q&A and Other Discussion

["Garnizov, Ivan (RRZE)" <>]

Hi Marian,

In my opinion the most tricky part would be to make the perfSONAR services 
operate with the public IP. Probably you have succeeded with this.
It seems to me that you are on the right way, but now you would also have to 
apply some iptables magic and modify the IP header on the way out so that the 
router on the gateway does not get confused when receiving the packages.

Please note I am just sharing thoughts here and my suggestions are not based 
on real experience.

Best regards,
Ivan

-----Original Message-----
From: 

 
[mailto:]
 On Behalf Of Marian Babik
Sent: Mittwoch, 9. Dezember 2015 16:12
To: 

Subject: [perfsonar-user] virtual bridge

Hi,
we're trying to run network measurements using perfSONAR at a cloud provider 
that has some tricky network setup.

Provider's VMs have both private and public IP addresses, but the public IP 
is not configured directly on the VM (I have only eth0 with 192.168.4.105). 
However traffic is routed correctly for the public IP address, if I open a 
port locally, I'm able to connect to it via public IP address from a remote 
location (so there is some virtual bridge that forwards connections, 
connecting to opened ports on 175.6.57.170 works fine from remote locations).

If I try to run owping from this box to a working perfSONAR, I get denied 
with the following in the owamp log :
Dec  9 15:27:47 ps-lt owampd[2232]: FILE=sapi.c, LINE=303, Connection to 
([ps-lt.cern.ch]:861) from ([175.6.57.170]:34659)
Dec  9 15:27:47 ps-lt owampd[2232]: FILE=sapi.c, LINE=466, 
ControlSession([ps-lt.cern.ch]:861) accepted from 
userid(nil):([175.6.57.170]:34659)
Dec  9 15:27:47 ps-lt owampd[2232]: FILE=sapi.c, LINE=610, Test Denied: 
OpenMode recieve_addr(192.168.4.105) != control_client(175.6.57.170)

I tried to setup sub-interface and added 175.6.57.170 as eth0:1, however this 
doesn't get routed since the virtual bridge is dropping such packets (as it 
should).

My question is if there is way how I can either configure perfSONAR to think 
it has public IP address not visible locally (175.6.57.170), or alternatively 
get the other end to accept connections when receive_addr is not the same as 
control_client address ?

Thanks,
Marian