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docs/config.en.md

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+[Documentation](../README.md#documentation) → Configuration Reference
+
+-----
+
+[Читать на русском](config.ru.md)
+
+# Configuration Reference
+
+Vitastor configuration consists of:
+- Configuration parameters (key-value), described here
+- [Pool configuration](config/pool.en.md)
+- OSD placement tree configuration
+- [Inode configuration](config/inode.en.md) i.e. image metadata like name, size and parent reference
+
+Configuration parameters can be set in 3 places:
+- Configuration file (`/etc/vitastor/vitastor.conf` or other path)
+- etcd key `/vitastor/config/global`. Most variables can be set there, but etcd
+  connection parameters should obviously be set in the configuration file.
+- Command line of Vitastor components: OSD, mon, fio and QEMU options,
+  OpenStack/Proxmox/etc configuration. The latter doesn't allow to set all
+  variables directly, but it allows to override the configuration file and
+  set everything you need inside it.
+
+In the future, additional configuration methods may be added:
+- OSD superblock which will, by design, contain parameters related to the disk
+  layout and to one specific OSD.
+- OSD-specific keys in etcd like `/vitastor/config/osd/<number>`.
+
+## Parameter Reference
+
+- [Common](config/common.en.md)
+- [Network](config/network.en.md)
+- [Global Disk Layout](config/layout-cluster.en.md)
+- [OSD Disk Layout](config/layout-osd.en.md)
+- [OSD Runtime Parameters](config/osd.en.md)
+- [Monitor](config/monitor.en.md)
+- [Pool configuration](config/pool.en.md)
+- [Inode metadata in etcd](docs/config/inode.en.md)