Intro
Solr can be run on Windows Azure. See the tutorial Getting Started with Solr/Lucene on Windows Azure for an example of how to configure and host Solr/Lucene in Windows Azure using multi-instance replication for index-serving and single-instance for index generation with a persistent index mounted in Azure storage.
The tutorial explains how to install the Windows Azure SDK and create a Windows Azure subscription and storage account, with links to installation instructions for the Java JRE and Solr/Lucene. After the prerequisites are handled, the tutorial covers how to install and deploy a sample Windows Azure Solr/Lucene project hosted on Github.
Typical scenarios addressed with this sample are commercial and publisher sites that need to scale traffic with increasing query volume and need to index a maximum of 16 TB of data requiring a small number of index updates per day.