8.6.3 Configuring External Time Source After the new CTN configuration process is completed, you can configure the ETS. In this  example, we define two HMCs that are configured as NTP server for ETS (see Figure 8-33 on  page 177). If your CTN is configured with more than two CPCs, you can set individual ETS for  PTS and BTS. Complete the following steps: 1. Open the  Manage System Time  task and select  Configure External Time Source  from  the STP ACTIONS list.  2. The Select the system on which to modify the External Time Source (ETS) window opens.  Select the CPC for which to modify the ETS setting. We select  MUSCA  (the only CPC in  this CTN) in this window. Click  NEXT  to continue (see Figure 8-45). Figure 8-45 Select the system on which to modify the External Time Source (ETS) window 184  IBM z14 Model ZR1 Configuration Setup