perfSONAR User Q&A and Other Discussion

[Trond Endrestøl <>]

On Fri, 6 Oct 2017 13:22+0200, Trond Endrestøl wrote:

> On Fri, 6 Oct 2017 13:18+0200, Trond Endrestøl wrote:
> 
> > 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!
> 
> It's even better adding "yournode.fqdn yournode" to the loopback 
> addresses in /etc/hosts.

Sorry guys, the latter is just bad advice. My bad. I stand by my first 
suggestion of adding a dummy IPv4 address and making the hostname 
resolvable via /etc/hosts.

Users running IPv4 only or dual-stack will only know the difference 
once they turn off IPv4.

-- 
Trond.