Merce

Cloud hosting

Code in the clouds

  • Everybody's talking about systems in the cloud these days. We love cloud technology, and our prior experience in virtualisation of systems and storage has prepared us somewhat for this new technology (at least, for IaaS clouds).

    We have experience in setting up EC2 servers on Amazon AWS. We have found it difficult to use stock AMI (Amazon Machine Image) in some cases, and have built our own AMI with the OS kernel and tools we need. In some situations, with Linux kernels, we have encountered challenges with configuring of IP packet filtering, because there are interactions between the kernel modules which AWS supports and the modules needed for IP packet filtering.

    Data backups are done using Amazon S3. Primary disk storage is on Amazon EBS, which supports snapshots. By backing up EBS snapshots on S3, excellent data backups can be provided. There is even provision to back up data across seismic zones, since AWS makes the physical zone of their infrastructure visible to customers. Therefore, the EC2 virtual machine and its EBS storage may be in the UK and the S3 backup copy can be stored in Singapore, protecting against natural calamities.

  • We can therefore host customer projects on AWS cloud infrastructure. This becomes extremely attractive for short-term deployments, e.g. during the period when the customer's in-house infrastructure is not yet ready. It is also attractive to customers who do not maintain in-house server infrastructure.

    We can also offer the service of configuring an AWS server as a backup to an on-premise server for high availability purposes. The active server may be placed in our customer's data centre, and a second server with identical software stack can be installed on an EC2 instance. Database replication etc. can be set up between the two. In case of active server failure, the AWS-based server can be brought into active service. This is very attractive in terms of being cost-effective, because AWS will only bill for hours when the EC2 server is active, and a backup server does not need to be kept active 24x7.

RELATED READING