Perseus Software Configuration Changes in 2014

Links below were the guides to what was done. It should be assumed that the indicated steps were executed by root.

First attempts at improvement, in 2014...through the installation of CentOS 7 and the creation of disk partitions on the added 1TB drives.

The first round of major work was informed by these two websites:
How to Install CentOS 7 Step by Step with Screenshots
How to Use Fdisk to Manage Partitions on Linux

Two software RAID-0 sets were created, on two pairs of 1TB HDDs. Ultimately this plan ran into trouble and was abandoned! (What happened?)

How To Sync Your System Time to Hardware Clock Consistently (the manual update step was done in CentOS 7)
Configuring the system clock (some additional checks for CentOS 7)
Timezone behavior for date and hwclock

date -u  # means "show system time adjusted to UTC", can be quite different from...
hwclock -u  # means "show rtc time adjusted to CURRENT TZ, assuming rtc is kept in UTC".
hwclock --localtime  # should be correct on Perseus - assumes rtc is kept in localtime
cat /etc/adjtime  # to see whether LOCAL or UTC is the default for "hwclock --show"

Installed Intel Composer XE 2013 from l_fcompxe_2013.0.079.tgz, to get ifort 13.0.0 20120731. License file was copied over from Fedora.

Why does my Ethernet not work unless I log in and explicitly enable it? - because some system files needed to be changed...

# first, followed advice to use the Network Manager from the GNOME Desktop
# then, edited the en*0 file below, to enable the en*0 interface upon boot
grep ONBOOT /etc/sysconfig/network-scripts/ifcfg-enp130s0f*
/etc/sysconfig/network-scripts/ifcfg-enp130s0f0:ONBOOT=yes
/etc/sysconfig/network-scripts/ifcfg-enp130s0f1:ONBOOT=no

Question 4 at the above link also discusses the HOSTNAME setting in /etc/sysconfig/network (optional, if DNS already has the right name).
The "hostname" command returned "localhost.localdomain", and it seemed better to make the hostname match DNS: "perseus.lps.cornell.edu".

First this was addressed in Fedora: Change hostname in Fedora 17 (close enough to Fedora 15!)

cp -p /etc/sysconfig/network /etc/sysconfig/network.bak
# ...edited /etc/sysconfig/network to change localhost.localdomain to perseus.lps.cornell.edu
cat /etc/sysconfig/network
NETWORKING=yes
HOSTNAME=perseus.lps.cornell.edu
NTPSERVERARGS=iburst

How to change hostname on centos 6.5? (says to use the 127.0.0.1 address in /etc/hosts)

cp -p /etc/hosts /etc/hosts.bak
echo 127.0.0.1 perseus.lps.cornell.edu perseus > /etc/hosts.tmp
cat /etc/hosts >> /etc/hosts.tmp
mv /etc/hosts.tmp /etc/hosts
systemctl restart NetworkManager.service
# logged out, logged back in

BUT: /etc/hostname HAD to be localhost.localdomain!?! CentOS 7 won't assemble an attached RAID if its HOMEHOST doesn't match hostname!



Last updated on 5/1/17 by Steve Lantz (steve.lantz ~at~ cornell.edu)