ClearDB FAQs

Got questions about Aventra™ or ClearDB? We’ve got answers.

Check out the list of common questions and answers below to get started. We also encourage you to become part of the ClearDB community to participate in all things ClearDB, such as getting quick access to support and connecting with ClearDB experts.

Aventra IRON Questions

General ClearDB Questions

ClearDB Multi-Tenant Database Questions

Common ClearDB Basic or Pro series Questions

Common ClearDB Billing Questions

Aventra IRON Answers

What is an Aventra IRON enabled AMI?

Aventra IRON enabled AMIs operate in-memory with disk-based persistence. Specifically, they “optimize” storage I/O, delivering 3x to 30x increases in IOPs performance. Aventra IRON for EC2 ensure your applications and services are processed as close to the compute power of the selected EC2 instance type as is possible, yet they are still safe from any disruptions in RAM.

All Aventra IRON enabled AMIs are completely self-contained. You do not need to install any other software to make Aventra IRON enabled AMI’s boost the compute, memory and storage workload performance of your applications and services. In fact, Aventra IRON enabled AMI’s are simple to deploy, enabling you to harness the power of larger EC2 instance types from smaller EC2 instance types quickly. See Aventra IRON Deployment Guide here for instructions and use cases.

What is in-memory caching and how does it help my applications?

The in-memory caching, disk-based persistence of Aventra IRON enabled AMIs can be used to vastly improve latency and throughput for many read-heavy, compute-intensive, and high-concurrency workloads. In-memory caching improves application performance by storing critical elements of data in memory for low-latency access. Aventra IRON enabled AMI’s are simple to deploy, enabling you to harness the power of larger EC2 instance types from smaller EC2 instance types quickly.

How durable is Aventra IRON in-memory capabilities?

Aventra IRON enabled AMIs are fully durable. They automate Amazon’s Elastic Block Store (EBS) persistent block level storage for EC2 instances as replicated across multiple EBS Availability Zones. Aventra IRON’s automation features; along with their in-memory, disk persistent capabilities; protect you from component failure, offering both durability AND high-availability. In essence, with Aventra IRON enabled AMIs, you get n+2 physical disk redundancy that automatically rebuilds memory on restart. And equally valuable, you do not have to continuously configure and monitor these features to get their benefits, which provides time to focus on other important tasks.

What are the best uses for Aventra IRON enabled AMIs?

You can use the in-memory, disk-based persistent, high-IOPs performance features of Aventra IRON enabled AMIs like any other physical disk or solid-state drive. The difference is you are using Aventra IRON enabled AMI’s to significantly, and cost-effectively improve latency and throughput of your applications and compute-intensive workloads. For instance, Aventra IRON volumes can be used as primary storage for data that requires frequent updates, such as system drives for database applications; for throughput-intensive applications that perform continuous disk scans; for high-concurrency operations; or for computationally-intensive calculation workloads. In essence, those applications that require fast in-memory data, a highly available cache or a message broker will see significant performance improvements with Aventra IRON enabled AMIs; enabling you to harness the power of larger EC2 instance types from smaller EC2 instance types. See Aventra IRON Deployment Guide for specific use cases and deployment recommendations.

Are there any use cases not suitable for Aventra IRON enabled AMIs?

Anything you can do with an EC2 instance type, you can do better with Aventra IRON enabled AMIs.

How do I get started using Aventra IRON enabled AMIs?

Aventra IRON enabled AMI’s are available through Amazon’s Web Services Marketplace. To access the AWS-Marketplace, visit to sign into the marketplace or register with Amazon Web Services. Search for Aventra IRON enabled AMIs once you are in the AWS-Marketplace. When you find the Aventra IRON enabled AMI best suited for your use-cases and workloads, subscribe to it in one of two ways:

  1. AWS Marketplace – you can launch an Aventra IRON enabled AMI quickly with AWS’s 1-Click deployment feature, or
  2. Amazon EC2 Launch Wizard – you can search for Aventra IRON and launch your selected Aventra IRON enabled AMI directly from the Wizard. For more information about the Wizard.

Once you have launched your Aventra IRON enabled AMI, follow the simple instructions in the Aventra IRON Deployment Guide to realize its cost-effective performance value.

What AWS-EC2 instance types are available for use with Aventra IRON enabled AMIs?

Aventra IRON enabled AMIs are configured specifically for the unique characteristics of Amazon Web Services Elastic Cloud Compute (EC2) instance types. Click here […insert URL…] for the current list of EC2 instance types available for use with Aventra IRON enabled AMIs. Feel free to contact Aventra Support Services if you do not see the EC2 instance type you need.

How will I be charged and when does billing for Aventra IRON enabled AMIs begin and end?

You pay only for the EC2 instance type and Aventra IRON enabled AMI hours you use. There is no setup or minimum fee. Pricing is per hour consumed for each EC2 instance type and Aventra IROn enabled AMI. Partial hours consumed are billed as full hours. Billing commences after the trial period concludes, and continues until you terminate the use of Aventra IRON enabled AMIs. If you no longer wish to be charged for your Aventra IRON enabled AMIs, you must terminate their use to avoid being billing for additional hours.

Do Aventra IRON enabled AMI prices include taxes?

Except as otherwise noted, Aventra IRON enabled AMI prices are exclusive of applicable taxes and duties, including VAT and applicable sales taxes. For customers with a Japanese billing address, use of the Asia Pacific (Tokyo) Region is subject to Japanese Consumption Tax.

How do I get support for my Aventra IRON enabled AMIs?

We are here to help, so please contact Aventra Support Services if you need assistance with your Aventra IRON enabled AMIs.

Does ClearDB, Inc. collect any user data from its Aventra IRON enabled AMIs?

No, user data is NOT passed from Aventra IRON enabled AMIs to ClearDB, Inc.

Do Aventra IRON enabled AMIs run on Windows Server?

No. Currently, Aventra IRON enabled AMIs use Linux-based AWS-EC2 instance types only.

How do I check my current Aventra IRON enabled AMI usage?

Sign into your AWS account and click the “Dashboard” selection on the left of the screen. This will launch your Billing & Cost Management Dashboard. From this screen click the “Bill Details” link on the right for more information.

Are there any limits AWS places on the use of Aventra IRON enabled AMIs?

AWS defines certain usage limits by default to prevent users from accidentally creating too many resources and being charged for them accordingly. Your AWS account may reach one or more of these limits when using a large number of servers, backups or static IP addresses. See below:

  1. EC2 Instances – AWS has a limit of 20 instances per region by default. This includes all instances set up on your AWS account. To increase EC2 limits, request higher limits from AWS Support by selecting “Support” from your AWS account dashboard.
  2. Static IP Addresses – AWS sets a limit of five (5) static IP addresses per region. This includes IP addresses unassigned and current assigned to a server. To increase IP address limits, request higher limits from AWS Support by selecting “Support” from your AWS account dashboard.
  3. Snapshots – AWS default limit for all snapshots is 10,000 per region. To increase the limit on snapshots, request higher limits from AWS Support by selecting “Support” from your AWS account dashboard.

Common General ClearDB Answers

What is ClearDB?

ClearDB is a highly available MySQL database-as-a-service that runs in multiple cloud computing as well as in hybrid cloud/datacenter environments. It’s designed to eliminate the need to manage your own MySQL database. ClearDB provides specialized, highly available MySQL database clusters that are built around the premise of failure to ensure that your database is always online and fully available, 24/7. We use standard MySQL technology, with a layered software stack “wrapped around” to provide automatic, intelligent support so that you can focus on your application, not managing you database.

What does ClearDB do?

ClearDB provides MySQL database services for your applications in several different environments: in clouds, such as Amazon’s EC2 and Windows Azure, on-premise, such as in your data centers and offices, as well as a combination of the two, in our hybrid solutions. You can use ClearDB to store your database information for your application and service workloads.

How does ClearDB work?

ClearDB uses a combination of standard MySQL, mixed in with “master-master” replication as well as our own specialized layered software stack to provide a highly available MySQL database environment for your applications and services. Each cluster is geographically separated to ensure your database’s availability, even if an entire network, datacenter, storage, or system failure occurs. Combined with our high availability routing technology, we ensure that your database is always online and fully available, 24/7.

Why should I use ClearDB?

ClearDB is the only real high availability MySQL provider on the market today. Thousands of satisfied customers use our mature, proven software solution and 24/7 customer support to ensure that their database services remain online, no matter what. We’re also the only database as a service provider that currently offers an SLA-backed, 100% uptime guarantee. Combined with our solid operations practice, our expert engineers, and our dedicated customer support, you’re in good hands with ClearDB.

How does ClearDB compare to Amazon’s MySQL RDS?

Amazon’s MySQL RDS product provides a “standard MySQL” approach to database availability and performance. With RDS, you can define how many slave systems you would like and assign a single master server. While RDS is an interesting product, it does not solve a number of problems that plague application administrators and developers: how to ensure availability and not get a phone call at 3AM to re-point an application at a different server, or how to ensure that you don’t have to worry about things like master elections, or better yet – how to ensure that you don’t have to pay a huge amount of money for basic support. Finally, RDS restricts master-slave availability to a single region. Last year alone, a service outage caused an entire EC2 region to become unavailable, causing all of the RDS customers in that region (US-East) to go offline. Here’s how ClearDB solves these problems:

  1. We ensure that your applications are never interrupted with our proprietary SQL routing technology. So if a failure occurs, your application will simply continue to run as it should.
  2. Multiple master nodes ensure that things like master elections never interfere with your applications availability.
  3. Our geo-separated configurations ensure that no single region can cause a complete service outage for your applications.
  4. 24/7 customer care and technical support are bundled into our pricing, making ClearDB a much more affordable option than RDS.

ClearDB is 100% dedicated to ensuring the availability, performance, durability and security of your databases, both in-cloud and on-premise. Our service is backed by our 100% uptime SLA, and uses standard, unmodified MySQL to ensure that your applications operate as expected on our database platform. This ensures that you won’t be blind-sided by additional cost for having to re-tune your applications. Finally, ClearDB is much more cost effective than Xeround, mainly because our costs are lower than theirs. We didn’t re-invent the wheel, we simply put better tires on it.

Does ClearDB work in other environments than Amazon’s EC2?

Yes, we do! Our Basic or Pro seriess can operate in the following cloud environments:

  • Amazon’s EC2 (Worldwide)
  • Windows Azure (Worldwide)

Our multi-tenant database clusters currently operate in the following cloud environments:

  • Microsoft’s Windows Azure (Most sub-regions worldwide)
  • AppFog (US-East, EU-West)
  • (US-East, EU-West)
  • Heroku (US-East, EU-West)
  • IBM BlueMix (via EC2’s US-East, EU-West)

Does ClearDB have any on-premise/hybrid solutions?

Yes, we offer our Hybrid DB configurations, which enable us to provide you with a turn-key VM which can power your database in an on-premise environment, such as local data centers or offices. This on-premise VM connects to your Basic or Pro series in the cloud for true, 100% hybrid availability for things like scale-out for seasonal workloads, decision support jobs, etc. Contact us if you would like to know more about our Hybrid DB service offerings.

Does ClearDB offer any data enhancement/data cleaning solutions?

Unfortunately no, we do not. We are focused on providing database services for our customers, and have a strict “hands off” data policy to ensure HIPAA compliance as a data clearinghouse provider.

How does ClearDB scale in comparison to other cloud database services?

ClearDB scales by enabling you to select the type of database plan you would like to use, delivering on highly performant, durable clusters that are properly configured to ensure high performance. Our performance markers are defined by our service plans, or “tiers”. Each service tier uses larger resources, larger systems, more storage, more bandwidth, and more power for your database. For our enterprise customers, we offer scalable read pools. Combined with our front and back-end SQL routing technology, we enable your database to function more like a supercomputer, fanning queries out to each read pool, all while ensuring geo-separated, highly available data access.

Multi-tenant ClearDB customers can easily upgrade their database plans to higher multi-tenant plans in-place, without having to migrate data or update their application configurations to point to a different cluster. This makes scaling up easy!

What does ClearDB do if a database server fails?

ClearDB uses intelligent diagnostics technology to assess availability and database node health. In the event that a database node becomes unhealthy or has failed, our SQL routing technology will automatically re-route your connections to the secondary master node to enure that your applications and services remain online and available. In the background, our services will begin diagnosing the failed node. If a problem is identified that can be fixed automatically, our systems will “heal” the failed or unhealthy node and bring it back into service. Once the failed or unhealthy master node has resynchronized with the secondary master, our SQL routing technology will automatically switch back to it. During this process, your applications will never lose access to your database.

Can I lose data if a failure occurs?

In most cases, no. ClearDB uses durable storage (such as EBS on Amazon’s EC2, or Azure Drives on Windows Azure) for your databases and MySQL’s transaction logs to ensure that your data is available, even if a server instance fails or a storage outage occurs. In the event a server instance fails, we simply spin up a new instance and mount the durable storage from the failed instance onto the new instance and restore cluster services. Upon cluster synchronization, our SQL routing technology will automatically switch back to the failed node (if it has priority).

What is ClearDB’s SLA?

Simple. We offer an SLA-backed 100% uptime overall service guarantee on our production services. “Overall service guarantee” means that we guarantee that your database will be available on at least one master node, 100% of the time. See our SLA policy for more details.

I saw a system status notice about Azure recycle activities. What does this mean?

Please be advised that the Azure cloud occasionally undergoes routine recycle activities for maintenance purposes; you can read more about these activities here. If you have selected the Azure cloud, these events can cause some systems powering your ClearDB database(s) to go offline for a period.  While our failover features are designed to protect you against downtime, the Azure recycle activity may impact the performance of your ClearDB database(s) while in effect.  This is a temporary event, and all systems should automatically return to normal operational status once all recycles have completed.

If you see a notice about Azure recycle activities and your database appears to be offline, it’s possible multiple systems have recycled at the same time. While this is rare, if it occurs it may affect your ability to connect to your database. If your non-evaluation services are impacted in this way due to Azure recycle activities, please open a support ticket immediately in the ClearDB portal to gain assistance.

For customers with mission critical production applications, ClearDB offers Multi-Access Point (MAP) dedicated clusters that provide mitigation for these kinds of scenarios. With a MAP cluster, should your primary Azure region experience problems for any reason you can use Azure Traffic Manager to move your workload to a secondary Azure sub-region. This does require geo-distribution of your application, but this approach provides for an ultimate up-time and disaster recovery topology for vital production applications. Please contact for more information on custom dedicated clusters in Azure.

What is ClearDB’s data jurisdiction policy?

While we do offer support for a trans-atlantic cluster configuration, we also support data jurisdiction for services which require specific region boundaries. They are as follows:

  • Euro Zone: Dublin, London, Amsterdam
  • United States: San Francisco CA, Portland OR, Ashburn VA, Chicago IL, San Antonio TX
  • Pacific Rim: Hong Kong, Singapore, Tokyo

Does ClearDB offer 24/7/365 support?

Yes, we do, and at no additional charge. We’re committed to serving your MySQL database needs.

How do I get started with ClearDB?

Sign up for an account with us today!

When I use auto_increment keys (or sequences) in my database, they increment by 10 with varying offsets. Why?

ClearDB uses circular replication to provide master-master MySQL support. As such, certain things such as auto_increment keys (or sequences) must be configured in order for one master not to use the same key as the other, in all cases. We do this by configuring MySQL to skip certain keys, and by enforcing MySQL to use a specific offset for each key used. The reason why we use a value of 10 instead of 2 is for future development.

How do I manage my database(s) on ClearDB? Is there a phpMyAdmin or similar application that I can use?

We recommend that you use MySQL tools, such as the MySQL Workbench or the traditional mysql command line client. You can also use Sequel Pro and other MySQL GUIs to manage your database. For importing data into your MySQL database, we recommend that you use both the mysql command line client as well as the mysqldump database backup utility.

ClearDB Multi-Tenant Database Answers

Where can I get access to ClearDB multi-tenant services?

ClearDB Multi-Tenant database services are available through our Platform-As-A-Service partners:

Do limitations exist on ClearDB’s multi-tenant plans vs. ClearDB’s Basic or Pro series services?

Yes, in order to ensure the highest quality of service for our multi-tenant database customers, we enforce the following SLA policies for multi-tenant services:

  • Maximum Database Connections
  • Maximum Database Size
  • Maximum Queries Per Hour
  • Maximum SELECT Query Execution Time

The values for these SLA policies vary depending on the service plan in use. Larger plans have access to larger amounts of these resources.

How do I know that my database is secure in ClearDB’s multi-tenant service?

We utilize best-practice MySQL security enforcement as well as SSL communications security to ensure database security on our multi-tenant clusters, just as we do on our dedicated clusters. We also encrypt all backups on disk to ensure that your data is safe at all times in which it is not inside the database itself.

How fast is ClearDB’s multi-tenant service vs. it’s Basic or Pro series services?

Our multi-tenant database clusters utilize some of the largest instance types in the cloud to ensure high performance and availability for all of our multi-tenant database customers. However, due to the fact that many customers are using our multi-tenant clusters, CPU time and I/O bandwidth must be shared amongst all multi-tenant customers on each cluster. At times, this can potentially reduce the amount of performance that is available per database.

On the other hand, our Basic or Pro seriess provide 100% focused compute resources and bandwidth to your database, 100% of the time. This makes it possible for you to fully utilize the power and capability of an entire database cluster for your applications.

I need more space/power/resources than are available on ClearDB’s multi-tenant service plans. What should I do?

We recommend that you sign up for an account with us and purchase a Basic or Pro series for your database. This ensures that you get 100% dedicated power and no multi-tenant resource restrictions so that your application can scale as needed.

I need to migrate my data from another provider, such as Amazon RDS into ClearDB. How do I do that?

If you need to migrate your data from another MySQL provider, such as Amazon’s RDS, simply use the mysqldump utility in conjunction with the mysql command line client. For example:

mysqldump --single-transaction -u (old_database_username) -p -h (old_database_host) (database_name) | mysql -h (cleardb_host) -u (cleardb_user) -p -D (cleardb_database)

You’ll be asked for your old database host’s password first, then for the password of your new ClearDB database. Once you’ve authenticated to both hosts, the old database host will simply transfer your database into ClearDB.

If you need to migrate your data from another database provider such as Heroku Postgres, you can use the following methods:

  • Follow Heroku’s documentation regarding the use of taps or by using pgbackups to produce a SQL-neutral format that can be imported using the mysql command line client.
  • Use a rake task to migrate your schema only (if that’s all you need to migrate)

I suddenly cannot perform INSERT, UPDATE, or CREATE commands on my multi-tenant database. What happened?

This means that you have reached the size limit on your database. This typically happens with our free database plan, where a maximum of 5-10MB is allowed. In order to re-gain write privileges to your database, you’ll either need to delete data from it or upgrade your database to a larger plan.

If you are using our largest multi-tenant plan and have reached this point, we recommend that you create an account with us and purchase a Basic or Pro series system that meets your database needs.

I’m getting an error message saying that I have exceeded the ‘max_questions’ resource for my database. What can I do?

The max_questions resource is defined by how many queries you may issue to your database in an hour. Our free plans start with 3,600 queries per hour and increase to 18,000 upon purchasing a paid plan with us. Larger plans have larger QPH limits. We recommend that you upgrade your database with us to lift this limitation off of your database.

I received an error message saying that I have exceeded the ‘max_user_connections’ resource for my database. Why?

Each multi-tenant plan supports a maximum number of database connections that are allowed. This is to ensure the highest quality of service for all of the customers and databases that are on each multi-tenant cluster. If you receive this message, it means that you have reached your connection limit for the plan for which you are currently subscribed. We recommend that you upgrade your database to a larger plan to lift this restriction off of your database.

For some reason some of my longer SELECT queries are being cancelled or killed. What’s going on?

In order to maintain the highest quality of service for all of our multi-tenant customers, we limit the amount of execution time allowed for SELECT queries on our multi-tenant clusters. This ensures that no single customer can consume all of the available CPU and I/O resources on the cluster for more than the maximum time allowed. Most of our multi-tenant clusters restrict SELECT query execution time to 60 seconds.

How do I upgrade my current multi-tenant database to a larger plan?

Heroku Customers

If you are interested in upgrading to a larger multi-tenant plan, simply use the heroku addons:upgrade cleardb command to upgrade to the next plan up.

I need help figuring out a problem with my ClearDB multi-tenant database. Who do I need to contact?

First, please check this FAQ for a solution to your problem – the answers you’re looking for may already be here! 🙂

If you still cannot find a solution to your database problem, please feel free to contact us for assistance.

Common ClearDB Basic and Pro Series Cluster Questions

I need additional security options for my ClearDB cluster. How can I enforce client SSL (or x.509) authentication?

We operate our own CA, and we’ll be happy to generate x.509 user authentication certificates for your account. Please send us a support request (login required) to get x.509 certificates.

How long does it take to set up a new cluster for my business?

Our automated process for cluster spin-up takes around 30 minutes to complete. For non-automated spin-up operations, we require a 3 business day window to build your cluster for you.

My company is interested in using ClearDB, but we have service requirements that are larger than ClearDB’s service plans. Can we use ClearDB with a larger configuration than what is listed?

Yes, we do support configurations that are larger than the ones that we list on our website. If you would like to receive a custom quote from us for your database configuration needs, please send our sales team an email with your contact information so that we can begin discussing your database needs as well as set up a demo for your organization.

My business needs a HIPAA-compliant database-as-a-service provider. Is ClearDB HIPAA compliant?

With regards to being a signed business associate serving as a data clearinghouse provider, yes, we are HIPAA compliant with regards to PHA and ePHA protection. We also support safe harbor regulations regarding data jurisdiction. See our data jurisdiction answer for more details.

Why is ClearDB’s Basic or Pro series pricing different from it’s multi-tenant pricing?

ClearDB’s Basic or Pro series pricing differs from our multi-tenant pricing mainly because of the fact that we’re dedicating an entire cluster for you alone. This enables your business to operate using the full power and bandwidth of an whole ClearDB cluster, where our Multi-Tenant customers must share resources on the same cluster.

Common ClearDB Billing Questions

How does ClearDB do billing?

We bill our customers on a monthly basis. Dedicated customers are billed at a standard rate every month. Most of our multi-tenant customers are billed using our partners’ pay-per-use billing, which pro-rates their bill. Customers who operate billing through ClearDB are billed at a standard monthly rate.

What billing options are available for Basic or Pro series customers?

We support the following billing methods for dedicated customers:

  • Credit Card
  • Wire Transfers (Basic or Pro series customers only) with AR/AP

What billing options are available for multi-tenant cluster customers?

Most of our multi-tenant cluster customers’ billing operates through our PaaS partners. If you’re using one of our multi-tenant clusters with a paid plan, you’re already being billed for our services via the PaaS provider you’re using.

Why doesn’t ClearDB use pay-per-use billing?

It’s simple: most of our customers enjoy the fact that they know how much their bill will be at the end of each month, which eases the tension of working with us.

If we need to upgrade our database plan to a larger configuration, how does that affect our billing?

This depends on the larger configuration you’re upgrading to. For example, if you’re upgrading from one multi-tenant plan to another multi-tenant plan, you will be billed via our PaaS partner’s pay-per-use billing process. However, if you’re a Basic or Pro series customer and want to upgrade to a larger cluster, we will update your payment subscription or create a new subscription for you.