Apache Web Server application recovery

Apache with data replication

For a seamless recovery of your Apache servers, SteelEye Life Keeper from Open Minds guarantees to provide you with a complete disaster recovery solution ensuring that you maintain business continuity. Our high availability solutions will grant continuous data protection providing data replication as well as the monitoring of all your Apache servers to ensure failover through the Java GUI.

In a typical local configuration, data is replicated between the servers. Identical copies of the Apache Web Server configuration file, web documents, DSO modules (and their configuration files, if any), and the httpd executable reside in exactly the same locations on each server. MySQL databases are replicated between the active and backup servers. As there is no requirement for redundant servers, one possible scenario would be to have an active Apache server and an active MySQL server both acting as a hot backup to each other.

When the Apache hierarchy is switched over from one server to another, this particular httpd instance is stopped and the IP addresses are deactivated on the first server, then the IP addresses are reactivated and the instance started on the other server. Clients will then be automatically connected via TCP/IP to the identical web site on the other server.

Recovering Apache servers using Shared file systems

Apache web servers can be recovered using shared storage (below). The example below shows an active/active environment where the Apache server is acting as a backup for a SAMBA server. This eliminates the need to have a redundant server as a backup server.

Failover in an n+1 environment

Multiple servers can be protected simultaneously by setting up an N+1 configuration. The example below shows a typical server farm running multiple apache servers. These servers can be protected by a single backup server that will monitor all of the servers in the cluster. LifeKeeper allows up to 32 nodes in a cluster.

Disaster recovery to a remote site

To protect against a site disaster, failover to another site is achieved by recovering to server located in a separate location.

The scenario below shows data replication taking place across a WAN to a backup server in a remote location. When Apache fails over, the data is up to date.