One of the things that Adcap Network Systems does a lot of is Cisco Unified Communications System upgrades. And the upgrade to the newest version involves converting to virtual servers using VMware. The most common upgrade path is to replace the Cisco voice appliances with a Cisco UCS B series blade system. The issue we sometimes run into is that our customers may not have a storage system that meets the requirements for Cisco UC on UCS.
The upgrade then gets delayed because an expensive Fibre Channel storage appliance has to be procured, and in many cases this is an unforeseen expense, so it causes wailing and gnashing of teeth in the IT department. Because the system can start as a small, fast, and inexpensive system, then grow into a larger system with no hardware limitations, the Cisco Nexenta ZFS Storage System is a good option to solving this issue.
For Cisco Unified Communications on UCS, there are specific performance requirements for the storage system. And because Adcap’s UC upgrade designs are architected by Mike Cavanaugh, CCIE #4516 in Voice and Route/Switch, we follow his recommendations, which are to not only meet the IOPS specs, but to also use Fibre Channel if at all possible. A fast Fibre Channel storage appliance usually comes in at about $50k, and this is for the smallest version, with limited expandability and upgrade options.
Since most organizations don’t want to step into a shared storage system that has limited future use, they start looking at bigger and more flexible storage solutions. This usually puts them in excess of $100k for the features they need, and all of a sudden the UC upgrade project is put on hold until $100k of budget money can be shaken loose.
Enter the Cisco Nexenta ZFS Storage System. Because the NexentaStor software license is transferable, the organization can start with a small and fast system that meets the immediate needs of the UC upgrade. Then as the shared storage requirements grow, the system can be expanded with JBOD storage shelves, additional controllers can be added for High Availability, and all the other features available from NexentaStor can be implemented.
What would a small and fast storage system look like that would meet the needs of a Cisco UC on UCS upgrade? The specs are listed here http://docwiki.cisco.com/wiki/UC_Virtualization_Storage_System_Design_Requirements
NexentaStor is Supported for Cisco Voice
The Nexenta storage solution is fully supported for Cisco voice systems. From the Cisco link above:
“Note: Cisco provides storage networking and switching products that are based on industry standards and that work with storage array providers such as EMC, NetApp, and so forth. Virtualized Unified Communications is supported on any storage access and storage array products that are supported by Cisco UCS and VMware.”
See these links below. Both NexentaStor and VSA for View are supported by both Cisco and VMware:
- Nexenta is supported by Cisco on Cisco UCS – Nexenta NexentaStor and VSA for View are in the Cisco Solutions Catalog.
- Nexenta is supported by VMware – VSA for View Solution Brief (pdf link).
So, what type of NexentaStor system will meet the performance requirements of Cisco voice? Condensing the information from the Cisco article leads to general information of:
- Storage block size: 4K
- LUN Size: 500GB-1.5TB
- IOPS: ~200 IOPS per Cisco Voice application at 500 user design size
- Connectivity: Fibre Channel preferred
- Data types: CUCM storage access is on average 93-98% sequential writes with an IO block size of 4 kilobytes.
One example given of an approved storage design on that Cisco document is shown in this picture, and is a RAID group of five discs of 450G spinning at 15K.
The Adcap tested and certified design that meets this specification is based on the Cisco C240. The base solution includes:
- Cisco C240 value bundle server with:
- 64GB memory
- Emulex dual 8GB FC controller
- Cisco VIC 1225 dual 10GE CNA.
- 10 hard drives total. 2 for NexentaStor OS, 7 for RAIDZ2, 1 for spare.
- Using 300GB 10K RPM drives provides 2.1TB raw storage.
- NexentaStor software with Fibre Channel plugin.
- Adcap professional services for installation and configuration.
- 1 year manufacturer’s support from Cisco and Nexenta.
The budgetary price for the configured, installed, and supported system is $16k.
Based on experience, this is an acceptable price for an element of the Cisco voice system upgrade. Especially with the knowledge that the system has unlimited upgrade capability. For many Adcap customers, this provides them with the ability to get the UC upgrade done, and the Cisco UCS systems provides a platform for additional server virtualization.
It is also important to be able to upgrade the storage system in the future to add additional disk shelves and high availability by having two controllers. This is done with the Cisco Nexenta ZFS Storage System by adding a second Cisco C240 server, adding an external storage shelf accessible by both Cisco C240′s, and moving the data then the drives to the external shelf.
Then when ready for Virtual Desktop Infrastructure, the combination of Cisco UCS and Nexenta VSA for VMware View is an unbeatable combination of price and performance. Adcap’s design of Cisco UCS and Nexenta ZFS storage enables an affordable storage entry point with the ability to add capacity, redundancy, and performance as required to meet the requirements of the organization.
Author: Rolf Versluis
Last Updated: March 3rd, 2013 |