8464ch09_Oper.fm Draft Document for Review February 7, 2020 3:15 pm Meanwhile, host commands that are sent to virtual devices in peer clusters can continue with  full read and write access to all volumes in the library. Write Protect Mode is used primarily for  client-initiated disaster recovery testing. In this scenario, a recovery host that is connected to  a non-production cluster must access and validate production data without any risk of  modifying it. Note:  FlashCopy is enabled by using the Library Request Host Console ( LI REQ )  command. A cluster can be placed into Write Protect Mode only if the cluster is online. After the mode is  set, the mode is retained through intentional and unintentional outages and can be disabled  only through the same MI window that is used to enable the function. When a cluster within a  grid configuration has Write Protect Mode enabled, standard grid functions, such as virtual  volume replication and virtual volume ownership transfer, are unaffected. Virtual volume categories can be excluded from Write Protect Mode. With R5.0, up to128  categories can be identified and set to include or exclude from Write Protect Mode by using  the Category Write Protect Properties table. Also, write-protected volumes in any scratch  category can be mounted as private volumes if the Ignore Fast Ready characteristics option  of the write-protected categories is selected.  Note:  Up to 128 categories can be added per cluster when all clusters in grid operate at  R5.0 or later level of code. The following settings are available: Write Protect Mode does not affect standard grid functions, such as virtual volume  replication or virtual volume ownership transfer. The settings that are available in the Write  Protect Mode page are listed in Table 9-10 on page 495. GLYPH<SM590000> Write Protect Mode settings 494  IBM TS7700 Release 5.0 Guide