perfSONAR User Q&A and Other Discussion

[Trond Endrestøl <>]

On Fri, 6 Oct 2017 12:59+0200, Trond Endrestøl wrote:

> On Fri, 6 Oct 2017 09:48-0000, Kashif Mohammad wrote:
> 
> > I was also having the same problem with Cassandra not talking to 
> > other components. It looks like that it is a problem with firewall. 
> > I disabled firewall and its working now.
> 
> Well, yes and no. Running these commands made it eventually work on an 
> isolated system with IPv4 and IPv6 addresses assigned to the NIC:
> 
> systemctl stop    firewalld
> systemctl disable firewalld
> shutdown -r now Preventive reboot after disabling firewalld.;sleep 1;logout
> 
> Systems running with IPv6 only, not so much.
> 
> Further testing shows that the web browser determines success or 
> failure.
> 
> Access the web UI by specifying the system's IPv4 address, numerically 
> or as a domain name, and everything works; access the web UI by 
> specifying the system's IPv6 address, numerically or as a domain name, 
> and it all breaks. And happens in 2017?
> 
> I was hoping to avoid assigning IPv4 addresses to my perfSONAR nodes ...

A crude workaround is to:

1. Assign a private IPv4 address to the NIC, say 192.0.2.3/24 (TEST-NET-1).
2. Don't bother adding a default gateway for IPv4.
3. Edit /etc/hosts, specifying the IPv6 address prior to the IPv4 address:

2001:db8:dead:beef::3 yournode.fqdn yournode
192.0.2.3             yournode.fqdn yournode

Each node's internals are now able to translate yournode.fqdn to an 
IPv4 address and resume internal comms. Dear God, make it stop!

-- 
Trond.