Category Archives: CentOS

perfSONAR 4.0.2

perfSONAR 4.0.2 is out. The system as a whole is still remarkably wedded to IPv4. Dual stack is preferred over IPv6 only. It’s tough luck if you succeed 100 % with the latter. CentOS/anaconda supports IPv6 RDNSS when configuring the DNS settings. Now, if only Cisco IOS XE would allow me to enter a domain name while configuring RDNSS. The country of Norway is (again?) a valid selection in the perfSONAR web UI. Communities disappears when you edit system information unless you also reenter your communities. Test results are only shown in the web UI when you access the node by its IPv4 address. Only IPv4 results are shown in the web UI. I’m still looking for an IPv4 block to assign to my future perfSONAR nodes. I firmly believe complete independence of IPv4 is a noble goal for perfSONAR 5.

perfSONAR 4.0.1 on CentOS 7

I have been playing with perfSONAR 4.0.1 on CentOS 7, using the FullInstall iso image.

I should point out my intention of running perfSONAR with IPv6 only.

The first impressions aren’t that great. The web UI allows me to select Norway as my country of residence, but it doesn’t save the selected country. If I move to Northern Mariana Islands or to Oman, that’s fine. The main dashboard proudly proclaims: “Error loading test listing: Internal Server Error”. I have done nothing but follow the instructions to the letter. Maybe I should try the previous version and see how well that goes.

I won’t claim I know CentOS or any other Linux distros very well, I have stayed with FreeBSD for the past 18-19 years. I am amazed at the number of hoops we need to jump through to get networking ready in CentOS. In FreeBSD everything is usually placed in /etc/rc.conf, that’s one file. OK, some other stuff goes in their respective files. In CentOS you have one or more files for each network interface, and several lines of variables in each file. What forced the Linux community to make such poor choices?


Update 2017-10-05

Running perfSONAR as a XenServer guest forced me to specify inst.text as a bootoption. Consequently, I had to visit the package set submenu where I selected “Minimal install”. Selecting “Basic Web Server” made no difference. Selecting “Server with GUI” or “GNOME desktop” was a no-go.

In the name of science, I tried the previous version, perfSONAR 4.0. This one is worse than 4.0.1. The web UI isn’t UTF-8 aware and the pscheduler service isn’t running at all. Selecting Norway didn’t work either. I also noticed the selected communities are not saved permanently.


Update 2017-10-06

firewalld is mostly to blame for preventing access to the Cassandra NoSQL database. Run these commands to stop and disable firewalld:

systemctl stop    firewalld
systemctl disable firewalld
shutdown -r now Preventive reboot after disabling firewalld.;sleep 1;logout

perfSONAR and its components are remarkably wedded to IPv4. Users running IPv4 only, or dual-stack, will not notice any difference until they turn off IPv4 in favour of IPv6.

One crude workaround is to add a dummy IPv4 address to the NIC, say 192.0.2.x/24 from TEST-NET-1. Don’t bother adding a default gateway for IPv4.

IPADDR="192.0.2.x"
PREFIX="24"

Ensure the hostname resolves to the host’s IPv6 and IPv4 addresses, in that order, via /etc/hosts.

2001:db8::x yourhost.fqdn yourhost
192.0.2.x   yourhost.fqdn yourhost

Better yet, run dual-stack until the matter is resolved.