Following on from the EMC Unity Setup Guide this post will walk through the configuration of an EMC Unity array with iSCSI connectivity using the management web interface. Before beginning, ensure your Unity device is up to date by following the EMC Unity Update Guide. The EMC Unity is also available as a Virtual Storage Appliance.
The EMC Unity hybrid and all flash storage range implements an integrated architecture for block, file, and VMware VVOLs powered by the Intel E5-2600 processors. The Disk Processor Enclosure (DPE) leverages dual storage processors and full 12-Gb SAS back-end connectivity to deliver high levels of performance and efficiency. Disk Array Enclosures (DAE) are added to scale out capacity up to 3 PB top end. There is concurrent support for native NAS, iSCSI, and Fibre Channel protocols whilst the unit itself takes up less rack space than it’s competitors. Unity arrays can be managed from the HTML5 web client, or through the CloudIQ service, and offer a full range of enterprise storage features. For more information see the Unity platform white paper.
Some considerations when creating storage pools; typically we want to configure less storage pools to reduce complexity and increase flexibility. However configuring multiple storage pools may be required if you want to separate workloads for different I/O profiles or use FAST Cache. When sizing a storage pool remember that all data written to LUNs, file systems, and datastores is stored in the pool, as well as configuration information, change tracking, and snapshots. Storage pools must maintain free capacity to operate, EMC recommend at least 10%.
You will need to make design decisions based on your environment around storage pool capacities and configured RAID protection. The Unity range offers RAID 1/0, RAID 5, or RAID 6 configured at storage pool level. EMC generally recommends smaller RAID widths as providing the best performance and availability, at the cost of slightly less useable capacity, e.g. for RAID 6 use 4+2 or 6+2 instead of 10+2 or 14+2. Unity automatically reserves 1 out of every 30 drives of the same type for use as a hot spare, you can reduce the number of hot spare drives by decreasing the number of individual drive types.
Unity arrays use the first 4 drives to store configuration information and critical system data, these are known as the system drives and run from DPE Disk 0 through to DPE Disk 3. The system drives cannot be used as hot spares but can be added to storage pools in smaller configurations, if no other disks are available. The usable capacity of system drives is reduced by around 100 GB, therefore storage pools utilising system drives should use a smaller RAID width. For larger configurations with high drive counts EMC does not recommend using the system drives as heavy client workload may slow down management operations. This restriction does not apply to all-flash.
Browse to the management IP address of the Unity array configured during installation. If you have not changed the admin password the default login is admin Password123#.
The welcome dashboard gives an overview of health and capacity. Note the icons in the top right hand corner. The first symbol shows the overall system state, if there are no issues this will be a green tick. The second icon lists active jobs and the third any active alarms. Next is the settings menu, logged in user menu, and help.
Let’s start by opening the settings menu using the gear icon. The Software and Licenses page lists the licensed enabled features. To install a license click Install License and upload the .lic file provided by EMC. You can also view system limits, install language packs, software updates, and disk firmware.
The Users and Groups page can be used to add local users or an LDAP identity source.
Use the Management page to configure NTP servers and DNS. The host name and management address can also be changed here if required as well as optional services such as Unisphere Central (centralised management), remote logging, and encryption.
The Storage Configuration page allows for configuration of FAST cache; FAST cache extends existing cache using enterprise flash drives to provide instant access to frequently used data. You can also view the spare disks in the system, but it’s best to come back to this after we’ve configured our storage pool.
Configure auto-support on the Support Configuration page by entering the support credentials and contact details. Make sure you use the EMC support account where the support contract is associated.
The Access page lists the iSCSI (Ethernet) and FC ports. Double click the port to view further details, all ports should be connected and green.
For Ethernet ports it is good practise to create link aggregation where more than one port is used for the same traffic, e.g. iSCSI data, or replication. Aggregating ports together pools the resources to create a highly available configuration, iSCSI or other services then use the port aggregation group to distribute I/O and provide redundancy. Select the first port for the group and click Link Aggregation, Create Link Aggregation. You can add or remove additional ports by selecting the port and clicking Link Aggregation, and Add to Link Aggregation or Remove from Link Aggregation.
Configure email alerts, and SNMP traps if required, using the Alerts page.
Next we’ll go through the menu options in the left hand navigation pane.
The System View page lists basic system information such as the model, serial number, and software version. If any hardware issues are detected they will be listed here.
The Performance page shows IOPS and bandwidth , you can also create I/O limits.
The Service page shows a number of service related tasks and logs, as well as any technical advisories issued by EMC. Auto-support functionality should already be enabled as we configured it earlier using the Support Configuration page of the Settings menu. The support contract will auto-populate once refreshed providing the correct support settings have been entered.
The Hosts page allows for configuration of network hosts, such as Windows or Linux machines, for storage access. An individual host can be added, or a subnet or netgroup; to allow access to multiple hosts or network segments. The VMware page provides a single workflow for adding vCenter servers and ESXi host discovery. Virtual machine and VMDK information can also be imported.
For block storage resources you must register initiators using the Initiators tab. Initiators are servers initiating Fibre Channel or iSCSI sessions, and are identified by a unique World Wide Name (WWN) or iSCSI Qualified Name (IQN). The link between the initiator and the port on the storage system is called the initiator path; an initiator can be associated with multiple initiator paths. At this point for iSCSI paths to show up iSCSI interfaces must be configured on the Block page, see the Storage section above for further details. For FC paths the appropriate zoning on the FC switch must be complete for the initiator paths to be seen by the storage system.
The Data Protection section gives you two ways of protecting data on the array. The first is Snapshots; snapshots are used to create point in time copies of your data. There are 3 built in snapshot policies with different retention periods, or you can create your own by clicking the add symbol.
The second option is Replication, replication allows data to be copied to a different Unity array or Virtual Storage Appliance, on or off-site. To facilitate replication you must first create an interface by clicking the Interfaces tab and the add symbol. Chose an Ethernet interface, or link aggregation group, to use and configure the network settings. Next click the Connections tab and the add symbol. Enter the details of the remote Unity system to be a replication target and the connection mode; asynchronous replication, which takes an initial copy and then only updates with incremental (changed) data (recommended for most use cases) or synchronous replication, which takes full copies of the data at each replication interval. Finally configure replication on the storage resource you wish to replicate, as outlined under the Storage section below.
To configure replication see the Configuring EMC Unity Replication post.
Before using any disks in the system they must be allocated to a storage pool. When creating storage pools take into consideration the notes in the Architecture section above. To create a storage pool click Pools and the add symbol. Assign disks to the storage pool and select a RAID configuration, a storage pool can be made up of 2 performance tiers (types of disks) with different RAID types.
The Unity array is able to provide both block level and file level storage. For block level resources click Block and iSCSI Interfaces. Use the add button to add iSCSI interfaces for use with block level storage, chose the interface(s), storage pool, and configure the networking settings. LUNs can be created and mapped to a host, subnet, or netgroup using the LUNs tab.
For file level resources click File and NAS Servers, click the add symbol to create a NAS server, chose the interface(s), storage pool, configure the networking settings, and select the sharing protocols to use. It is good practise to create at least one NAS server each on SPA and SPB, and distribute resources evenly. Once your NAS servers are ready you can create File Systems, and then SMB shares or NFS Shares using the appropriate tabs.
During the creating of storage objects such as LUNs or file systems, you have the option to configure snapshots and replication. These features can also be configured at a later date by selecting the storage object and clicking the edit icon. Snapshots can be configured using one of the built in policies or creating your own under the Data Protection section above. When creating replication sessions you need to specify a replication schedule and target.
The VMware page can be used to configure VVOLs, read more about this at Configuring VVOLs with EMC Unity.
Events and Support
The Events page lists all alerts from information to critical, as well as a record of all jobs that have been initiated on the device. The Support page provides links to documentation, training, and support.