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This page can be skipped if you intend to only work with a single machine.

The Network Time Protocol (NTP) is used to synchronize the clocks of all computers in the CPM lab.The Ubuntu ntp package should already be installed from the previous step.

Edit the NTP configuration sudo nano /etc/ntp.conf and insert your NTP server. In our case, this is:

pool ntp1.rwth-aachen.de iburst
pool ntp2.rwth-aachen.de iburst

Restart NTP using sudo service ntp restart.

Verify that NTP works correctly by running ntpq -p.

Under the st (stratum) column sould be at least one "1". This indicates a successful synchronization.

cpm@cpm-MS-7A94:~$ ntpq -p
     remote           refid      st t when poll reach   delay   offset  jitter
==============================================================================
 ntp1.rwth-aache .POOL.          16 p    -   64    0    0.000    0.000   0.000
 ntp2.rwth-aache .POOL.          16 p    -   64    0    0.000    0.000   0.000
 0.ubuntu.pool.n .POOL.          16 p    -   64    0    0.000    0.000   0.000
 1.ubuntu.pool.n .POOL.          16 p    -   64    0    0.000    0.000   0.000
 2.ubuntu.pool.n .POOL.          16 p    -   64    0    0.000    0.000   0.000
 3.ubuntu.pool.n .POOL.          16 p    -   64    0    0.000    0.000   0.000
 ntp.ubuntu.com  .POOL.          16 p    -   64    0    0.000    0.000   0.000
*ts-1.rz.rwth-aa .GPS.            1 u  281  512  377    0.486   -1.204   0.122
+ntp2.rwth-aache .GPS.            1 u  187  512  377    0.563   -1.082   0.139

The website https://time.is/ is also useful for checking the clock synchronization.