perfSONAR User Q&A and Other Discussion

[Aaron Brown <>]

Hey Andi,

My guess is that the host itself is NAT’d from the outside world, but there’s 
a 1:1 mapping between the external interface and the internal one. 
Unfortunately, bwctl doesn’t currently support this model as it passes around 
the IPs for the testing tools bind to. 

Cheers,
Aaron

On Sep 2, 2014, at 4:48 PM, Andi Bergen 
<>
 wrote:

> Oh my, that is discouraging.
> iperf -s -B 142.104.17.140 -p 6019
> bind failed: Cannot assign requested address
> (in fact: can't bind to any address).
> Without the bind option it works and accepts connections from external
> sources though.
> Andi
> 
> 
> On 2 September 2014 12:34, Aaron Brown 
> <>
>  wrote:
>> Hi Andi,
>> 
>> Can you run this on the server host?
>> 
>> iperf -s -B 142.104.17.140 -p 6019
>> 
>> Cheers,
>> Aaron
>> 
>> On Sep 2, 2014, at 2:34 PM, Andi Bergen 
>> <>
>>  wrote:
>> 
>>> Hi Aaron,
>>> 142.104.17.140 is the server host. Checking with netstat -nlp, port 6019 
>>> is not used by anything.
>>> 
>>> The public ip address of the VMs is visible and accessible from outside 
>>> their private network.
>>> Oh, I forgot to mention, sorry:
>>> - if I run iperf on these ports, it works.
>>> - Running iperf on the client and bwctl on the server does connect. 
>>> Nothing happens, but then ctrl+c on client does show that a connection 
>>> was made on the server (iperf).
>>> - Running bwtcl on the client to iperf on the server works (the returned 
>>> format is different).
>>> - logging in from an external network to the public IP address works.
>>> 
>>> We are using OpenStack to orchestrate the VMs.
>>> It might be an issue with openstack, because a traceroute looks somewhat 
>>> funny from 142.104.17.139 to the "server"
>>> traceroute to 142.104.17.140 (142.104.17.140), 30 hops max, 60 byte 
>>> packets
>>> 1  142.104.17.140 (142.104.17.140)  95.876 ms  95.797 ms  95.732 ms
>>> 2  * * *
>>> 3  * * *
>>> 4  * * *
>>> 5  * * *
>>> 6  * * *
>>> 7  * * *
>>> 8  * * *
>>> 9  * * *
>>> 10  * * *
>>> 11  * * *
>>> 12  * *^C
>>> 
>>> I hope that helps,
>>> Andi
>>> 
>>> 
>>> 142.104.17.139
>>> 
>>> On 2014-09-02 11:14 AM, "Aaron Brown" 
>>> <>
>>>  wrote:
>>> Hi Andi,
>>> 
>>> I see this error in the server logs:
>>> 
>>>> Sep  2 13:01:05 centos bwctld[122131]: FILE=endpoint.c, LINE=319, 
>>>> bind([142.104.17.140]:6019): Cannot assign requested address
>>> 
>>> 
>>> Does the 142.104.17.140 host have the address 142.104.17.140 configured 
>>> on it, or is it behind a NAT or something? I’m not sure why it wouldn’t 
>>> be able to bind to that address.
>>> 
>>> Cheers,
>>> Aaron
>>> 
>>> On Sep 2, 2014, at 1:40 PM, Andi Bergen 
>>> <>
>>>  wrote:
>>> 
>>>> Hi,
>>>> I am having problems getting the bwctl to run successfully between two
>>>> of my install locations.
>>>> 
>>>> I followed the steps outlined here:
>>>> https://fasterdata.es.net/performance-testing/perfsonar/ps-howto/level-1/
>>>> and have this installed on two VMs.
>>>> 
>>>> I downloaded the limits file from:
>>>> http://stats.es.net/sample_configs/bwctld.limits
>>>> (which does include a /16 address for our institution).
>>>> 
>>>> What doesn't work is running
>>>> bwctl -vv -c 142.104.17.140:4823 -f m -x -a 100
>>>> or bwctl -vv -c 142.104.17.140 -f m -x -a 100
>>>> 
>>>> However, running this TO any other machine (I found listed here
>>>> http://stats.es.net/ServicesDirectory/#search=es) works.
>>>> 
>>>> It also works just fine when using the internal IP addresses of these
>>>> machines since they are on the same network.
>>>> 
>>>> I checked that bwctl is bound on the external interface. And
>>>> connections are going through, but then fail (please see attached
>>>> /var/log/messages files for both machines).
>>>> 
>>>> All UDP and TCP ports are open for machines in the same security
>>>> group, as well as all ports I could find in the docs are open
>>>> otherwise. The ports mentioned in the log files are opened.
>>>> 
>>>> Attached are the /var/log/messages from the VM that is running the
>>>> test (client.log) and the machine that functions as the "server"
>>>> (server.log).
>>>> 
>>>> Did I follow the wrong instructions, or am I missing something
>>>> obvious? I am somewhat at a loss for what to check next...
>>>> 
>>>> Thank you,
>>>> Andi
>>>> ps.
>>>> Command line output from "client" bwctl -vv -c 142.104.17.140:4823 -f
>>>> m -x -a 100
>>>> (at a different time than the attached log files, but it is always the
>>>> same except the time stamps of course):
>>>> bwctl[122582]: FILE=bwctl.c, LINE=2931, Using 10.6.9.19 as the address
>>>> for local sender
>>>> bwctl[122582]: FILE=bwctl.c, LINE=2931, Using 142.104.17.140:4823 as
>>>> the address for remote receiver
>>>> bwctl[122582]: FILE=bwctl.c, LINE=2977, Available in-common: iperf 
>>>> nuttcp iperf3
>>>> bwctl[122582]: FILE=bwctl.c, LINE=3002, Using tool: iperf
>>>> bwctl[122582]: FILE=bwctl.c, LINE=3117, Requested Time: 1409679438.153914
>>>> bwctl[122582]: FILE=bwctl.c, LINE=3119, Latest Acceptable Time:
>>>> 1409680038.153914
>>>> bwctl[122582]: FILE=bwctl.c, LINE=3292,
>>>> Reservation(142.104.17.140:4823): 1409679448.061957
>>>> bwctl[122582]: FILE=bwctl.c, LINE=3156, Server '142.104.17.140:4823'
>>>> accepted test request at time 1409679448.061957
>>>> bwctl[122582]: FILE=bwctl.c, LINE=3292, Reservation(localhost):
>>>> 1409679448.061957
>>>> bwctl[122582]: FILE=bwctl.c, LINE=3185, Client 'localhost' accepted
>>>> test request at time 1409679448.061957
>>>> bwctl[122582]: FILE=bwctl.c, LINE=3359, BWLStartSessions: Failed
>>>> <server.log><client.log>
>>> 
>>