Attention VARs!!!

Are you currently in the planning and/or design phases of building a highly scalable and highly available XenDesktop virtual desktop infrastructure?

Are you planning to take advantage of the performance, scalability and reliability capabilities of SAN storage to store the virtual images (VHDs) that will be streamed to virtual machines hosting the desktops?

Are you spending a lot of time trying to find the best way to ensure that the infrastructure achieves the highest levels of performance, scalability, availability and manageability in order to realize the greatest return on your investment?

If so, please take a few minutes to read the following white paper: http://www.sanbolic.com/pdfs/HA_Options_for_Citrix_Virtual_Solutions.pdf.

This paper highlights the storage options most frequently considered by organizations looking to enable high availability for Provisioning Services™, or PVS™ (the underlying technology used to stream images on demand to virtual machines hosting virtual desktops).

Once you’ve finished reading the paper it will be obvious why, out of all the options available for enabling high availability for Provisioning Services, only Sanbolic Melio 2010 has proven to actually enhance Citrix XenDesktop!

Organizations that have deployed Citrix XenDesktop with Sanbolic Melio 2010 have achieved the following:

1. Simplified maintenance of vDisk images by consolidating all vDisks onto a single volume on SAN storage, with all vDisk changes available for streaming by multiple PVS Servers immediately, i.e., no need to replicate the vDisks to different PVS Servers to ensure vDisk consistency.

2. Enhanced I/O performance using stripe sets to leverage multiple storage controllers, caching and spindles, thereby improving the user experience.

3. Quick and seamless scale out by adding more PVS Servers or more storage resources on the fly, with little effort and no interruption in user productivity.

4. Enhanced utilization of storage resources to keep storage costs at a minimum.

5. Centralized management of storage resources as all physical disks are virtualized and managed from a single console that can be accessed locally or remotely.

6. Improved fault-tolerance via high availability of vDisks as well as the PVS database.

7. Protection for vDisks using VSS-based snapshots of shared volumes or individual vDisks, with the ability to mount snapshots on any PVS Server and browse through the snapshots quickly and easily via Explorer.exe.

If your interest in Sanbolic Melio 2010 is piqued by the information presented in the white paper and you’d like to see a live demonstration of how Melio 2010 enhances Citrix solutions, please contact us at sales@sanbolic.com and one of our sales representatives would be happy to schedule a demonstration for you.

For a more detailed look at how Sanbolic Melio 2010 optimizes Citrix XenDesktop, check out this paper: http://www.sanbolic.com/pdfs/Optimizing_Citrix_XenDesktop_VDI_Solutions_with_Sanbolic_Melio_2010.pdf, which explains how Melio 2010 enables the seamless scale-out of XenDesktop to allow organizations to extend the benefits of VDI to a larger percentage of their users.

To learn more about Sanbolic’s SAN-storage enhancing software, Melio 2010, please visit http://www.sanbolic.com. We’re confident you’ll see why Melio 2010 is the ideal choice for optimizing Citrix XenDesktop virtual desktop infrastructures.

And while you’re there, check out the many other solutions we enhance, such as scalable file and web-serving farms, highly available SQL Server clusters and enterprise-class server virtualization with Microsoft Hyper-V.

Sanbolic – Building better solutions with virtual shared storage!

Cheers,

Andy

It’s no secret that when it comes to telling Fairy Tales, the Russians have always had the brightest imaginations. My father studied Russian literature in graduate school and I can recall tales of Vasilisa the Beautiful, Peter and the Wolf, and other such fables that fostered my imagination at a young age. Today I would like to share a new story written by Andrey Ivanov from Moscow about the magic of a certain clustered file system. For those of you who can read Russia, enjoy…

Сказка перед выходными

By utilizing Sanbolic’s cluster file system Melio FS , LaScala Volume Manager, and AppCluster users can provide high availability and consolidation for SharePoint 2010. An update for AppCluster to be released in the next coming weeks will add a new feature that allows for grouping of databases (SharePoint requires that all the primary databases be located on the same server). This resource group can then be automatically failed-over to another SQL server in the event of a failure without the need for Microsoft Failover Clustering. For non-primary content databases AppCluster can provide this same capability as well as load balancing by distributing the different content database across different servers. AppCluster’s use of virtual IP’s allows this all to be done without requiring reconfiguration on the SharePoint server in the event of a fail-over. Additionally by using the Melio file system all SQL servers supporting SharePoint can utilize a single file system for database resources without the need for storage migration. Also Melio FS provides QoS components that allows users to allocate specific bandwidth guarantees to specific databases. These can be either the primary databases, additional content databases, or both. By using the LaScala volume manager users can expand their SharePoint database volumes on the fly without IO interruption and also mirror the data across multiple storage arrays allowing for a complete failure of a storage array while still providing access to the data. All of this comes in a single simple to install package and allows for quick deployment and simple administration.

Microsoft TechEd 2010, New Orleans, had incredible sessions and keynotes, such as Bob Muglia’s presentation on how to realize the benefits of cloud-based computing and Ted Kummert on the journey of building a platform for all data, a platform that spans tiers within the cloud from mobile platforms to data centers. Our Chairman, Bill Stevenson, did a well attended joint breakout session with Microsoft on how Sanbolic adds value to this strategy.

TechEd had lots of knowledge transfer, group collaborations and breakout sessions that it certainly made it well worthwhile to attend as a vendor or as an end-user. It was a place to meet the subject matter experts and strategists in such areas as de-duplication, security, business continuity, SharePoint, cloud computing and more.  And, it certainly was a place to have fun and party and meet new friends, such as the AvePoint party. They gave away a Ducati motorcycle; they also had the police escort us, and a live band, to a Bourbon Street bar.  In Massachusetts police escort you out of a bar, never into a bar.

I’m always amazed on the number of bright people from all around the world that can all convene at one location for a few days, and act as one giant, extended, courteous family, that get along with one another, and have a common purpose in technology and education for the real world.

Sanbolic extends a hart felt “Thank You”, for stopping buy our booth. We came away with many valuable contacts. What we noticed is that there were two categories of people that stopped by the our booth, those who knew us and stopped by to say hello and those people who knew nothing about Sanbolic and our advanced software technology and wanted to learn the benefits of our Melio 2010 software to their specific IT infrastructure, such as Virtualization (Hyper-V or VMware ESX),  Active-Active SQL Clustering, Citrix XenDesktop, Web Serving, Web Hosting, etc. Some stopped by our booth to just try their luck on winning our give-away prize, a Kindle, which by the way it was won by Gabriel Irizarry of Lockheed Martin.  Congratulations Gabriel!!!

These are a few, fun, TechEd 2010 pictures (or links) that I would like to share with you:

1) Customers at our booth.

2) Microsoft visits Sanbolic booth

3) People behind the Microsoft Costumes

4) The Sanbolic booth worker bees.

PS: On a sad note, if you ask me about the oil spill, yes, I saw the devastation off the coast, on my flight back to Boston.

Regards,
Mario

You are a user of SQL and love it but as you’re scaling out your encounter performance issues and perhaps management cost increases.

You wish the solution had even more “enterprise like features” so you could consolidate and dynamically migrate databases.

Maybe you are wishing to run all of your 48 or more SQL servers in the same cluster, and expand the storage volume on-the-fly without downtime.

Did you know that you can do this with Melio?

Did you know that we also create an environment where you can load-balance, apply QoS for a specific database, and back up it up independently?

Stay with the environment you are familiar with, utilize you servers fully (as they are all active), get better utilization of your storage, and create much more flexibility in your SQL environment.
Scale out without limitations and without operation interruption, and avoid additional management cost!

Download your evaluation copy of Melio (which includes AppCluster) today to Upgrade your Enterprise SQL Environment

 

Howdy all,

It’s time for another exciting episode of… “What Sanbolic Melio 2010 can do for you!”

And it’s all right here in this white paper – http://www.sanbolic.com/pdfs/HA_Options_for_Citrix_Virtual_Solutions.pdf.

If you’re a distributor, reseller, systems integrator, or current or potential Citrix customer in the planning and design phases of deploying XenDesktop VDI and/or XenApp application delivery solutions, the information found in this paper couldn’t be more timely. This paper describes the storage options most frequently considered by organizations looking to achieve high availability for their virtual desktops and XenApp servers streamed from Provisioning Services. After reading through the paper, it should be fairly obvious that of all the options, only the Sanbolic Melio 2010 option offers organizations high availability for virtual desktops and XenApp servers as well as:

1. Simplified maintenance of vDisks by consolidating all vDisks onto a single volume on SAN storage.

2. Enhanced performance using stripe sets (leveraging multiple storage controllers, caching and addition spindles) to improve the user experience.

3. Quick and seamless scale out for XenDesktop and/or XenApp infrastructures, with little effort and no interruption in user productivity.

4. Enhanced utilization of storage resources, allowing organizations to save money on disk drives.

5. Protection for vDisks using VSS-based snapshots of shared volumes or individual vDisks.

If your interest in Sanbolic Melio 2010 is piqued by the information presented in the white paper and you’d like to see a live demonstration of how Melio 2010 enhances these solutions, please contact us at sales@sanbolic.com and one of our sales representatives would be happy to schedule a demonstration for you.

Cheers,

Andy

 

Dear Polyserve/HP StorageWork EFS Clustered Gateway User,

Did you know that when HP dropped Transoft (9 or more years ago) we had a product that was similar to Transoft’s volume sharing software, and I called HP and asked what they were doing with the Transoft customers. I never got a straight answer. I asked them for the Transoft customer list so that we might be able to offer them an upgrade. They had ‘lost’ the list. Over time some of these customers did come to us.

Now history is repeating itself, as history does. HP’s acquisition of Polyserve some 3 years ago brought more customers our way as the awareness of need for clustered file system for scalable file serving went up. Polyserve started their development of their clustered file system for Linux at about the same time as we started ours for Windows. Eventually they ported to Windows to address needs in scalable file serving and SQL environments.

Now this offering is no longer (according to customer sources) available from HP and once again their customers have nowhere to go. We will offer them an upgrade – in every sense! Polyserve’s technology was slightly different than ours, but a good clustered file system (especially for Linux), but because it was ported from Linux to Windows it was never as seamlessly integrated into Windows technology as Melio is. Melio was built from the ground up for Windows and we use all native Microsoft tools and familiar interfaces.

All file serving and SQL customers that are using or were considering Polyserve, we welcome you to download Melio and see for yourself where the strength in our product lies:
• support for hundreds of nodes in the same cluster (Melio first to do)
• decouple databases and instances (Melio first to do)
• create one volume for all databases
• provide quality of serve at the database level (Melio first to do)
• cluster SQL databases for high availability
• automatically migrate SQL Databases between instances
• scale out servers or storage on-the-fly
• use physical or virtual servers
• faster failover times for minimum downtime
• snapshots and mirroring can create read only volumes for reporting (Melio first to do)

And best of all – Melio is shipping

So there is all this talk and noise about cloud in general and when we add the public vs. private cloud definitions I get overwhelmed (read annoyed). I did discuss how virtualization and cloud meet and where they make sense in a previous post.

One of the very interesting and compelling business reasons for all of this noise is that all of the vendors realize that this is not only about the infrastructure and application management, but also that it is the first time in decades that customers have the possibility of moving away from the typical Microsoft-based OS and application platform for good. It started some time ago when service providers started to offer web-hosting and web-mail and then added databases and other services for a small monthly fee. I moved my family’s website and mail server to such services in a heartbeat and I have never looked back. Most users probably don’t even know that there is no Windows, SQL or Exchange involved in the service they just selected and quite frankly it is irrelevant.

All I cared about is that it is cheap, available, backed up, and I don’t need to manage and maintain it. (oh, management – one of the largest costs in the datacenter today).

Today the webhosting industry and technology are far enough along that they can and will change the way we use computing dramatically while getting the same application results, speed and availability and business continuity without the huge infrastructure and management cost we have grown to dislike intensely.

Cloud can be seen as the next level of consolidation and flexibility that we are moving to after deploying virtualization and it does not matter if it is a public or private cloud, it is about the cost and management that we can reduce and it is opening a huge new opportunity for vendors and application developers to help address these issues.

One option is that you run this kind of dynamically deployable, highly available and agile virtualized infrastructure internally and call is it “private cloud”. The other option is that your ISP provides the apps and services that you or your company needs and they call it “ public cloud”. Either way, it doesn’t matter what the definition is and how it comes together; cloud is happening and after all the talking and opinionated noise – customers will get the benefit of more options, greater flexibility, and substantial cost savings.

The one major question is how much and how complex your move to the appropriate cloud would be?

For the ones that are interested in the more dynamical, flexible and agile Microsoft based cloud computing platform come and see us at Microsoft WWPC Booth 887.

Watertown, MA – There’s something lurking in the trees, watching your customer’s every move through the bush and it’s not me, it’s not the predator, and no, it’s not an Linux rep – it’s the Melio Monkey.

One thing that most of you probably don’t know about Sanbolic is that in our headquarter office we have a very agile monkey. I can say that all of the sales reps here want nothing more than to have the monkey sitting on their desk. I have personally acquired a bushel of fresh organic bananas to keep the monkey comfortable on my desk this week, but there is one problem, the monkey isn’t attracted by bananas, no, he prefers sales revenue.

In the 2010 season the monkey has been well fed and his arms are strong from swinging from desk to desk of the Sales Rep who has pulled in the most recent PO. Over the past year the monkey has been pleased with all of his virtual desktop deployments. These are delicious fruits for the monkey to feast on, however, in 2010 the Melio Monkey has been going ape shit for SQL deployments. Now that Melio 2010 supports SQL servers in active/active mode, the monkeys average meal has increased in size significantly and he’s been seen digging through SalesForce after office hours to get intel on his next accommodations. The $6 Billion SQL Market has the Monkey practicing his pull ups daily to train for all the orders he will have to carry. He’s sitting next to my monitor doing push-ups right now.

To learn more about the mythology behind the Melio Monkey please contact your Sanbolic Account Manager, who knows, the monkey may even be listening in on your conversations!

…oh and my desk is English Oak, so when this monkey turns into a 600 lbs Gorilla I’ll still have a special place for him next to my stapler.

/Alec

Hello all,

Andy here. As many of you have probably noticed while reading through recent technology articles, attending events or speaking with colleagues around the water cooler, it seems virtual desktop infrastructure, or VDI, has become quite the attention grabber lately, with all sorts of pundits touting both the pros and cons of virtualizing desktops.

In keeping with the latest trends, I thought it would be a good idea to take a few minutes to explain how Sanbolic’s Melio 2010 product suite enhances one of the more prominent VDI solutions currently on the market today, Citrix Systems’ XenDesktop. So let’s get to it!

About Citrix XenDesktop

Citrix XenDesktop is a comprehensive desktop delivery solution that allows organizations to extend the longevity of their current hardware, improve the return on their investments in new hardware and greatly simplify and enhance the management and delivery of desktops and applications. Using XenDesktop, organizations are able to manage and deliver hosted and streamed desktops throughout their enterprise environment on demand from a central console. Users can access virtual desktops (and any applications installed within the virtual desktops) running remotely on XenServer™ virtual machines and can access other applications running remotely on XenApp™ servers or streamed to their local devices.

As organizations consider the numerous benefits afforded by the rapid and dynamic delivery of desktops and applications and contemplate the migration of their current desktop infrastructure to this new desktop delivery paradigm, the folllowing key aspects of the solution should be thoroughly scrutinized.

Performance – Will users experience the same levels of desktop and application performance that they experienced using their local desktops?

The performance of hosted desktops and applications must be optimized to ensure that, from the user’s perspective, there are no discernable differences from desktops and applications running on their local machines.

Scalability / Scale-out - Will there be an easy way to build up and build out the virtual desktop and application delivery infrastructures as the needs of an organization continues to grow?

There must be a way to quickly and seamlessly expand the virtual desktop and application delivery infrastructures to support more desktops, more servers and more applications without introducing additional administrative overhead and without affecting the user experience.

Business Continuity - Will user productivity be maintained during unexpected failures or outages?

The continuous availability of hosted/streamed desktops and applications as well as all essential virtual desktop and application delivery infrastructure components (i.e., XenDesktop Delivery Controllers, Web Interface and XenApp servers) must be ensured to maximize user productivity.

Manageability - Will it be easier or more difficult to manage desktops and applications?

The virtual desktop and application delivery infrastructures must provide a simple, cost-effective way to manage desktop images and applications (i.e., consolidation and centralized management).

Data Protection - Will there be an easy way to protect desktop and VDI component images, i.e., backup and recover all images?

There must be a simple and effective way to backup and recover images for hosted and streamed desktops as well as XenDesktop Delivery Controllers, Web Interface and XenApp servers.

Storage considerations for Citrix XenDesktop VDI solutions

The driving engine behind XenDesktop is Provisioning Services™, also known as PVS™, an essential infrastructure component of the VDI solution that is used to stream images (vDisks) to target devices (i.e., virtual machines hosting virtual desktops, physical machines and various other systems that serve as the fundamental building blocks of a XenDesktop VDI solution, including the XenDesktop Delivery Controllers, Web Interface and XenApp servers). To ensure target devices maintain continuous access to PVS vDisks, Provisioning Services includes a high availability (HA) component that requires all Provisioning Servers have access to the PVS datastore containing the vDisks. Providing multiple Provisioning Servers with simultaneous read and write access to the PVS datastore is best accomplished using shared storage.

While there are numerous shared storage options available to enable PVS HA, readers who refer to the Virtualization Infrastructure Design section of the Citrix Systems’ white paper “Designing an Enterprise XenDesktop Solution” will note that Fibre Channel SAN storage is proposed for the Provisioning Services Infrastructure (PSI), as well as for every other infrastructure defined within the XenDesktop VDI solution, including the XenDesktop, XenApp and Hosted Desktop infrastructures. In fact, the only infrastructure for which SAN storage is not proposed is the PVS Remote infrastructure, for which local storage on the Provisioning Servers themselves is suggested in order to minimize the number of components necessary to extend the benefits of the VDI solution to remote offices.

Although the use of SAN storage is suggested in order to optimize the XenDesktop infrastructure showcased in the Citrix white paper, SAN storage has an innate limitation whereby only one device can have read and write access to a logical unit number (LUN) at any time. This means that multiple Provisioning Servers would not be able to share a single LUN containing the PVS datastore to enable high availability for vDisks. In fact, the only way to garner the benefits of both SAN storage and shared storage is through the use of a cluster file system, which provides the locking mechanisms necessary to allow multiple devices to share simultaneous read and write access to a single LUN at all times.

Besides underscoring the storage aspect of a XenDesktop VDI solution, the Citrix white paper also places strong emphasis on ensuring the scalability of a XenDesktop VDI solution, highlighting the need for their conceptual environment of 8,000 hosted and streamed desktops to be able to scale so that new farms, resource pools and servers can all be integrated into the infrastructure quickly and seamlessly (refer to the Conceptual Architecture section of the white paper).

So how can organizations take advantage of the benefits of SAN storage (i.e., performance, scalability and reliability) to achieve the levels of performance, scalability, availability and manageability necessary to ensure the greatest return on their investments in a Citrix XenDesktop VDI solution?

Answer: Deploy a Citrix XenDesktop VDI solution with Sanbolic Melio 2010 SAN software and SAN storage.

Optimizing Citrix XenDesktop VDI solutions with Sanbolic Melio 2010 and SAN storage

Sanbolic Melio 2010 is a feature-rich product suite comprised of various applications designed to work together to share, simplify and enhance SAN storage. At the core of Melio 2010 is an advanced, all-purpose, 64 bit symmetrical cluster file system that allows multiple devices to share simultaneous read and write access to LUNs on SAN storage and a cluster volume manager that simplifies the management of Melio shared storage while providing advanced functionality such as the creation of volume sets and stripe sets to improve storage performance, as well as dynamic volume expansion.

Using Sanbolic Melio 2010 and SAN storage, organizations can achieve all of the key aspects necessary to optimize a Citrix XenDesktop VDI solution:

• High performance via block-based access to storage and dedicated I/O paths
• Scalability to add more desktops, servers and storage quickly and seamlessly
• High availability for PVS vDisks and PVS databases
• Centralized management of storage resources for PVS datastores
• Data protection in the form of VSS-based snapshots for backup and recovery of vDisks

Melio 2010 SAN software installs quickly and easily on the Provisioning Servers and works with industry-standard server and SAN hardware, allowing the servers to share concurrent read and write access to a single LUN containing the vDisks within minutes. And best of all, Melio 2010 does not introduce any of the complexities or constraints associated with file-based shared storage solutions that often have an adverse affect on system performance, scalability and availability.

For many organizations, it was only shortly after commencing with the test phase of a Citrix XenDesktop VDI solution that performance and scalability issues arose, stemming from the use of file-based shared storage to support the Provisioning Services Infrastructure. These organizations turned to Sanbolic to help them design a VDI solution that incorporated the use of shared SAN storage to address each of the key aspects emphasized in the Citrix white paper (i.e., performance, scalability, availability and manageability) in order to optimize the solution and ensure a faster and greater return on their XenDesktop investments.

Using file-based storage, organizations that attempted to provision additional virtual machines to expand their existing hosted desktop infrastructures often encountered performance degradation as a result of the locking contention issues incurred by CIFS and NFS in mid to larger size file-sharing environments and the shuttling of storage operations over the same network used for vDisk streaming. Implementing more Provisioning Servers to stream vDisks to additional desktops taxed the file-based storage and network infrastructure even further, making it extremely difficult, if not impossible to scale the VDI solution to meet future needs while maintaining the high levels of performance necessary to ensure a rich user experience.

Sanbolic Melio FS works with block-based storage and thus, does not rely on CIFS or NFS to access data. Dedicated I/O paths are established between each Provisioning Server and SAN storage via Fibre Channel or iSCSI, thereby offloading storage operations from the LAN. This approach allows organizations to quickly and seamlessly add more desktops and more servers to their hosted desktop and Provisioning Services infrastructures, respectively, without impacting system performance.

For other organizations testing XenDesktop with file-based shared storage solutions, it became apparent that individual failures of the components making up these storage solutions introduced the potential to cause wide-spread disruptions in user productivity, particularly when the vDisks were stored on a file share hosted by a single server or on a NAS device. Attempts to address the single points of failure associated with these solutions required the use of additional components and more complex configurations in the form of Windows Failover Clusters or clustered NAS devices, both of which had a negative impact on performance due to the additional traffic levels presented to the network infrastructure. In addition, the active/passive operational mode of Windows Failover Clustering had a significant effect on overall system performance as only one Provisioning Server was able to access the drive containing the vDisks at any given time. This prevented organizations from maximizing network throughput when multiple Provisioning Servers streamed vDisks to target devices in tandem as all other servers that did not have direct access to the drive containing the vDisks were forced to access the vDisks through the one server that did have direct access to the drive in order for the load-balancing feature of PVS HA to be leveraged.

Some organizations made other efforts to work around the single points of failure associated with file-based shared storage solutions by assigning a separate LUN to each Provisioning Server. However, this approach added significant overhead to the management of vDisks as every time a change was made to the contents of a vDisk, the updated vDisk had to be copied to each LUN in order to ensure that each Provisioning Server streamed the most current version of the vDisk to target devices. The ability to scale their XenDesktop infrastructures was also affected as every time a new Provisioning Server was added to support an increase in the number of devices, an additional LUN had to be created, forcing IT administrators to copy vDisks to a greater number of LUNs each time a change was made to the contents of a vDisk. Lastly, poor utilization of both network bandwidth (the updated vDisk had to be copied over the LAN between Provisioning Servers) and storage resources (more LUNs with relatively low utilization levels) were experienced with this approach.

Using high performance, highly scalable, highly available and easy-to-manage shared storage provided by Sanbolic Melio 2010 and SAN storage, these organizations were able to achieve all the key aspects of an optimized XenDesktop VDI solution. Block-based access and dedicated bandwidth to shared storage for solid performance; the ability to add more desktops and more Provisioning Servers to the hosted desktop and Provisioning Services infrastructures quickly and seamlessly; the ability to add more storage resources on the fly to expand storage capacity and improve I/O performance; increased system resiliency in the form of fault-tolerance for target devices as all Provisioning Servers maintain read and write access to both metadata and vDisks when one or more servers fails unexpectedly; simplified management of desktop and VDI component images as only one LUN is necessary to store all vDisks, with changes to the contents of vDisks automatically and immediately available to all Provisioning Servers; and image protection in the form of VSS-based snapshots, allowing IT administrators to backup and recover vDisks at any point in time.

In conclusion, deploying Citrix XenDesktop with Sanbolic Melio 2010 SAN software and SAN storage offers organizations a high performance, highly scalable, highly available and easy-to-manage virtual desktop solution that allows IT administrators to focus their time and energy on managing their virtual desktop infrastructures and not the backend storage responsible for optimizing the VDI solution.

I hope this installment proved useful in explaining how Sanbolic Melio 2010 enhances Citrix XenDesktop VDI solutions. As always, please let me know if you have any questions.

Andy