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Another general principle is that PowerHA SystemMirror checks only what is being configured at configuration time and not the whole configuration. PowerHA SystemMirror checks the whole configuration at verification time. 

For example, when adding an HMC, you check only the new HMC (verify that it is pingable, at an appropriate software level, and so on) and not all  of the HMCs. Checking the whole configuration can take some time and is done at verify and sync time rather than each individual configuration step. 

## General verification 

Table 6-10 shows the general verification list. 

<img src='content_image/978656.jpg'>

## HMC communication verification 

Table 6-11 shows the HMC communication verification list. 

<img src='content_image/978657.jpg'>

