An alarm is generated in the ISM if the File system for logs is not mounted.
create a 170 GB LUN and map it to the File Engines. After that run "scanbus" from "Storage Resources > Data Disks". After the 170GB LUN is added in the datadisks of the File Engine, wait for a few minutes. The file system automatically picks up this storage space as the file system data storage pool. After this the alarm also disappears and the logs storage space is set.