ProCKSI

= Time Synchronisation =
The system time on all nodes must be synchronized as
a) data is written/read on/from a common, shared file system or even expires after a certain period of time and must be deleted, and
b) system logs are maintained independently but entries must be able to be associated with each other.

• Add your own time server to ''/etc/ntp/ntpservers'': {{{
  128.243.21.16 #marian.cs.nott.ac.uk
  128.243.21.17 #robin.cs.nott.ac.uk
  128.243.21.18 #tuck.cs.nott.ac.uk
  128.243.21.19 #pat.cs.nott.ac.uk
  }}}

• Modify ''/etc/ntp.conf'' in order to permit systems on the subnet to synchronise with this time service: {{{ # -- CLIENT NETWORK -------
  restrict 192.168.199.0 mask 255.255.255.0 nomodify notrap
  broadcastclient
  }}}

• Modify ''/etc/ntp.conf'' and add further time servers: {{{ # --- OUR TIMESERVERS -----
  server 128.243.21.16 #marian.cs.nott.ac.uk
  restrict 128.243.21.16 mask 255.255.255.255 nomodify notrap noquery
  server 128.243.21.17 #robin.cs.nott.ac.uk
  restrict 128.243.21.17 mask 255.255.255.255 nomodify notrap noquery
  server 128.243.21.18 #tuck.cs.nott.ac.uk
  restrict 128.243.21.18 mask 255.255.255.255 nomodify notrap noquery
  server 128.243.21.19 #pat.cs.nott.ac.uk
  restrict 128.243.21.19 mask 255.255.255.255 nomodify notrap noquery
  }}}

• Make the NTP daemon start at bootup. Enter at the command line of the master node and each slave node: {{{
  /sbin/chkconfig --add ntpd
  /sbin/chkconfig ntpd on
  }}}

• Start the NTP daemon. Enter at the command line of the master node and each slave node: {{{
  /sbin/service ntpd start
  }}}