Sushobhan has been with HP Software for thirteen years. He is an Expert Technologist and part of Customer Assist Team for the Storage Resource Management group.
Guest post by Sushobhan Das, Customer Assist Team, HP Software
Efficient utilization of data center resources is the new mantra. Unlike the compute and network resources in a data center, storage resource follows a ‘consume and hold’ utilization pattern. As the storage becomes a resource that is consumed in a centralized and virtualized manner, every level of storage configuration creates potential for storage to become lost.
Under these circumstances, reclaiming and re-deploying unused storage resources becomes a significant contributor for increasing utilization levels (often from 30-40 percent to 60-80 percent). This in turn, increases Return on Investment in Capital Assets and reduces Cost of Operation. If you have experienced this scenario, I bet you are looking for a tool to help.
In many instances, we carve out a storage pool in a Storage System or allocate LUNs (Logical Unit Number) to hosts that are never used or underused. In other instances, we may have assigned more storage space in a host’s volume manager volume group (e.g., VxVM Disk Group) than what we need in near term. This hidden treasure is spread across management domains throughout the data centers. It is a herculean task for administrators to locate this unused space without a tool.
HP Storage Operations Manager is here
Loaded with analytics in the form of dashboards, Inventory Views, Reports, etc., finding hidden unused and underused storage space has never been easier. HP Storage Operations Manager (SOM) provides this handy sources of information to help you in identifying storage resource systems and hosts with reclaimable storage.
Logical Unmapped Storage: Logical unmapped storage is the total size of LUNs created in a Storage System but not presented to any host. This capacity value applies to Storage Systems.
Logical Unallocated Storage: Logical Unallocated Storage is the total of free size in storage pools. This capacity value applies to Storage Systems.
Hosts with Unused Storage: Unused storage is the total size of unused LUN present in a host. This unused storage can be reclaimed straight-away unless there is application present in the environment that uses raw disk or partition. This capacity value applies to Hosts. It is often termed as ‘whitespace’.
Unused Volume Group Capacity: Unused Volume Group Capacity is the free space available in volume groups of volume manager configured in a host. Symantec Storage Foundation is an example of volume manager used in hosts. This capacity value applies to Hosts. It is often termed as ‘greyspace’.
Viewing Logical Unmapped Storage
In Storage Operations Manager, click on Storage Systems pie of Environment Summary dashboard pane from the Dashboards (Analytics) workspace. This launches Storage System Capacity dashboard which has Top 10 by Logical Unmapped Storage table bar graph (Figure 1) that lists the top 10 storage system having LUNs that are not mapped to any host. This is very handy information when you are looking for reclaiming and redeploying storage resource space to hosts.
Figure 1: Top 10 by Logical Unmapped Storage table bar graph
Logical Unallocated Storage
In the Storage System Capacity dashboard, the Top 10 by Logical Unallocated Storage table bar graph (Figure 2) lists the top 10 such storage resource systems with deployable storage space size. Based on your need, choose the storage system and provision the desired storage space to the hosts. With HP Storage Operations Manager, you don’t need to wander around anymore for a suitable array with space.
Figure 2: Top 10 by Logical Unallocated Storage table bar graph
Logical unmapped storage and logical unallocated storage data for all applicable storage systems is available in the Storage System Capacity table of Storage System Capacity dashboard. Export this table into CSV (right-click on any row of the able, choose ‘Select All’ and then choose ‘Export to CSV) and let Storage Administrator to start with reclaiming unused storage space.
Hosts with Unused Storage
Unused storage refers to storage space available in a host in the form of one or more LUNs (Logical Unit Number) on which neither a file system has been created nor added to any host volume manager volume group. In Storage Operations Manager accomplish this by, clicking on Hosts pie of Environment Summary dashboard pane from the Dashboards (Analytics) workspace. This launches Host Capacity dashboard which has Top 10 by Unused Storage table bar graph (Figure 3) that lists the top 10 hosts having unused storage along with size. So, here it is.
Figure 3: Top 10 by Unused Storage table bar graph
Now click on a host from this bar graph and the Host dashboard is displayed. In the Unused Storage table bar graph (Figure 4), name of reclaimable LUNs with Storage System name is displayed. Now after the Server Admin gives green signal, we are good to go to delete or redeploy.
Figure 4: Unused Storage table bar graph
Unused Volume Group Capacity
Unused Volume Group Capacity refers to storage space available in host volume group from which no volume has been created yet. In the Host Capacity dashboard, the Top 10 by Unused Volume Group Capacity table bar graph (Figure 5) lists top 10 such hosts having unused storage along with possible reclaimable space size.
Figure 5: Top 10 by Unused Volume Group Capacity table bar graph
Now click on a host from this bar graph and the Host dashboard is displayed. In the Unused Volume Group Capacity table bar graph (Figure 6), Volume Groups along with available space that can be reclaimed is displayed. Information of the amount of reclaimable space for all of the applicable hosts is available in Host Capacity table of Host Capacity dashboard. Export the table into CSV (right-click on any row of the able, choose ‘Select All’ and then choose ‘Export to CSV) and give this list to Server Admin to explore further action.
Figure 6: Unused Volume Group Capacity table bar graph