Xapi is the xapi-project host and cluster manager.
Xapi is responsible for
- aggregating hosts into a single entity (a “resource pool”)
- allocating VMs to hosts
- managing shared storage
- recoverying from host failure (“High-Availability”)
- preparing for site failure (“Disaster Recovery”)
- providing the XenAPI XMLRPC interface
- upgrading pools
- hotfixing hosts
- reporting bugs
- The XenAPI interface must remain backwards compatible, allowing older
clients to continue working
- Xapi delegates all Xenstore/libxc/libxl access to Xenopsd, so Xapi could
be run in an unprivileged helper domain
- Xapi delegates the low-level storage manipulation to SM plugins.