Leostream
Virtual Host Desktop Controller
Access Control and Management for Remote Access
Features:
Web Access to Virtual Hosted Desktops with Fine-Grained Access Control
You can give each user their own Virtual Hosted Desktop (VHD) computer running on a centrally-hosted Virtual Machine (VM). They access it using their standard web browser and a remote desktop viewer. Leostream's policy-based access control gives you fine-grained control over the way in which users can access and alter the Virtual Desktops.
Hot Backup of Virtual Hosted Desktops
You can automate backup and restoration of both running and stopped Virtual Desktops. You can store images on vmfs partitions that are local to the host server, or remote NFS and Windows shares as a backup set.
You can modify VHDs during restoration by giving them a new Virtual Machine Name, Windows Machine Name, and Domain.
Failover for Virtual Hosted Desktops
You can protect against failure of a host server by automatically restarting affected Virtual Desktops on another host.
Persformance Monitoring and Reporting
Leostream's Virtual Hosted Desktop Controller provides real-time monitoring of, and reporting on, VHDs via their RDC connection. You can choose to receive alerts by email or via SNMP.
Virtual Hosted Desktop Pooling
You can arrange for each user to be assigned a VHD from the appropriate pool at log-on. Each VHD is returned to pool at log-off or after a preset period of time
Virtual Hosted Desktop Self-Service
Users can browse a catalog of VHDs, select one and then request a copy. If required, each request can be approved by a supervisor before being created and assigned to a user.Functionality Explained
Web Access to Virtual Hosted Desktops with Fine-Grained Access Control
You can give each user their own VHD computer running on a centrally-hosted VM. They access it using their standard web browser and a remote desktop viewer such as Microsoft's Remote Desktop Connection (RDC) -- no additional end-user software is required.
Leostream's policy-based access control extends existing authentication systems, such as LDAP or Microsoft's Active Directory, to give you fine-grained control over the way in which users can access and alter the VHDs.
Hot Backup of Virtual Hosted Desktops
According to a schedule specified by you, the Leostream Controller automatically takes a snapshot of the disk image of a running or stopped VHD, compresses it, and stores it on a VMFS partition that is locally-attached to the host server, or on a remote NFS or Windows share.
A disk snapshot is taken by putting the virtual disk into read-only mode, and caching further disk writes in a REDO log. The disk image is then copied and compressed as it is written to the storage system, along with a manifest file that contains the VHD's meta-data.
After the disk image has been copied the cached disk writes are applied using an iterative write process that ensures that the virtual disk cache is not filled up faster than it can be written back to the disk image. Once the cache has been emptied it is removed and the disk returned to its non caching mode.
Each VHD has a backup set that allows point in time recovery, along with automated recycling of images in a backup set.
The VHD can either be restored exactly as it was backed up, with information such as the origin host stored in as meta-data, or it can be modified (given a new Virtual Machine Name, Windows Machine Name, Domain) so as to create a new VHD.
Failover for Virtual Hosted Desktops
If a host server fails then all the VHDs running on that host are affected. The Controller provides a rapid response to host server failures by automatically restoring the affected VHDs to their previous state on another host.
The Controller achieves this by monitoring host servers continuously. If one fails to respond to a preset number of pings, then the VHDs running on it are also checked before initiating failover.
During failover a suitable destination host server is identified, the cached configuration files for the affected VHDs are copied to the new host server, the relevant virtual disk images are remapped to the new location, and the VHDs are returned to their status prior to failure.
Performance Monitoring and Reporting
The Controller monitors the status of network connections to the VHD such as the RDC port.
If a running Virtual Desktop does not respond to the network queries then the Controller generates an alert via email or SNMP.
The performance of individual VHDs and the host servers can be monitored via the Controller web interface.
Reports on all aspects of the Controller can be extracted via web query into applications such as Microsoft Excel.
Virtual Hosted Desktop Pooling
Virtual Hosted Desktops can be placed in a number of individual "pools". Users that log-on are given a machine from the appropriate pool according to the user profile.
The Virtual Desktop can be returned to the pool at a preset time, such as the end of the session.
Virtual Hosted Desktop Self-Service
When users need access to a range of Virtual Desktops rather than just being assigned one or two, then an automated approval process provides a means of regulating the number of VHDs created while still giving end-users a quick and easy method of requesting new machines.
Each user simply browses a catalog of VHDs, selects one and then requests a copy. The appropriate supervisor accepts or rejects the request. If accepted then the VM is created with an optional expiry date, and assigned to the user. If rejected the user has the opportunity to revise and re-submit the request.
Interfaces
The Controller provides external interfaces for: Microsoft Active Directory, LDAP, XML-RPC control API, Controller logging, IBM Autonomic Computing, Web query and SNMP.
Compatibility
The Leostream system comprises the following components:
- Leostream Controller: Runs as either a VM, or as a Windows application. Manages VMs running under VMware ESX, GSX for Windows, and Microsoft Virtual Server 2005 R2.
- The VM version requires 1.5Gbytes of memory and 700Mbytes of hard disk space, as well as a bridged network connection.
- It is compatible and complementary with VMware VirtualCenter.
- The Windows version requires a clean install of Windows Server 2003.
- Each Controller is capable of managing up to 25,000 VMs and 2,000 host servers. The performance is determined by the number of simultaneous operations per second. A single operation could be stopping a VM or receiving one sample of performance data from a host. A VM running on a moderately loaded 4 CPU host should handle 20 to 50 operations a second. Other configurations can handle up to 250 operations a second.
- Host Agent: A Host Agent is installed on the destination host server running the virtualization software. Two versions are available, one for machines running Windows and one for machines running VMware ESX Server;
- The Leostream Host Agent for Windows is compatible with VMware Workstation 5.x running on Windows XP (any service pack), VMware GSX 3.x and Microsoft Virtual Server 2005 R2 running on Windows Server 2003 (any service pack).
- The Leostream Host Agent for ESX is compatible with VMware ESX Server v2.5 (v3.x).
Deployment
To deploy the Leostream system, download the VirtualController either as a VM disk image, register it with the virtualization software, and start it, or simply install the Windows application.
Then install the appropriate Host Agent on each host server and set the IP address of the VirtualController. The Host Agents will auto discover all of the virtual servers and report them.