Hosting Service Level Agreement (SLA)
stSoftware hosted systems have many monitoring, backup and disaster recovery options
Back-ups & Redundancy
All databases are backed up and transferred off site nightly.
As part of the document storage process files have a SHA-1 (Secure Hash Algorithm 1) hash calculated and then the files are compressed and encrypted. The SHA-1 and the encryption keys are stored in the client's database. The compressed encrypted documents are stored on multiple file server nodes in the cluster. Each night the encrypted documents are replicated off site.
Disaster Recovery
We can provide Disaster Recovery (DR) services or environments according to individual client's needs. An example is our DR Backup Service to Client Premises;
DR Backup Service to Client Premises
DR Backup Service to Client Premises & Automated Monitoring is available as an additional service to all hosted clients. This is an automated nightly DR service that provides our hosted clients with the full benefits of a fully managed cloud service with the surety of their system including data and source code being backed up to their own internal server. The DR backup also performs a daily restart of the DR application to ensure the application is operational and ready.
Heart Beat Monitoring
We have automated heart beat monitors which checks the health of the servers and a number of background tasks. In addition to checking the list of known tasks database read & write actions are performed and the available disk space is checked. If the heart beat monitor itself takes more than 5 minutes to run an alert is sent. The heart beat monitor runs every 15 minutes.
Hardware Replacement
The standard hosting package gives the client access to a system hosted on the stSoftware server cluster. The dedicated server cluster is hosted in Australia and includes a 2 hour hardware replacement guarantee upon receiving notification of hardware failure.
http://www.digitalpacific.com.au/hosting/dedicated-hosting/dedicated-servers/
Note hardware is one of many elements involved in restoring production availability after a hardware outage, full production availability will be 2 hours hardware replacement plus time to reset server/database settings and restore data from backups, then restart server.
Network and server availability
99.99% Network up time guarantee for non scheduled downtimes
We use Australian web hosting for our standard hosting of our server cluster with 99.99% network up time guarantee for non scheduled downtimes. Up time guarantee is for networks and excludes scheduled downtimes for incremental upgrades and upgrade fall back restarts or hardware replacement.
Scheduled Downtimes for Incremental Upgrades of staged production environments
Our client systems hosted on our server cluster operate within three staged production environments which are incrementally upgraded through an automated continuous integration system. This is called our agile continuous delivery pipeline. The three separate staged production environments have different upgrade schedules requiring brief scheduled downtimes. The disruption of these downtimes is minimized in two ways;
- We utilise a rolling restart between our cluster of servers to ensure a higher availability is maintained during the upgrade: site disruption is virtually uninterrupted to the viewer, active users may experience slower speeds and active file uploads may be disrupted at the moment of restart
- The scheduled upgrade releases for the production environments are deployed at low use times
Downtimes for Fall Back Restarts
When we do an install, it's a complete clean install and we copy the configuration from the previous release. This allows us to rapidly fall back to the previous release by changing the symbolic link and doing a rolling restart of the server cluster. The decision to do a fall back to the previous release is based on performance indicators (24 hour system monitoring & user reporting).