perfSONAR User Q&A and Other Discussion

[Mark Feit <>]

Alex Hsia writes:

 

There shouldn't be any firewall blocking access to simplestream and the host is using the default perfSONAR default host level firewall rules, i.e.:

 

I did some additional poking around and found the cause:  the hosts involved have mixed IP stacks.

 

Nettest is single-stack, so its FQDN has an A record only; sdmz-perfsonar-40g is dual-stack and has both.  Because most flavors of Linux will prefer IPv6 if available, sdmz’s FQDN will get an AAAA record first and the listening socket opened will be IPv6.  Nettest won’t be able to see that.  You can force your way around this by adding the “--ip-version 4” switch when running the troubleshooter or specifying IPv4 addresses explicitly.

 

The simplestream test and simplestreamer tool were originally written for use during development, but it’s become clear the diagnostics it produces aren’t as helpful as they could be to end users.  While I’m at it, I’ll probably make some adjustments to the troubleshooter to spot this situation and either warn about it or take steps to avoid it.  I’ve opened a couple tickets on these issues and should have enhancements out with 4.2.0:  https://github.com/perfsonar/pscheduler/issues/850 and https://github.com/perfsonar/pscheduler/issues/851.

 

--Mark