Precise certificate generation

[pve-docs.git] / pmxcfs.adoc

diff --git a/pmxcfs.adoc b/pmxcfs.adoc
index 9d88763b5bb96b4535be98aa41f9a068e78f7354..7b9cfac0d4faa0b51506f7d0a5f41389dc2182ef 100644 (file)
--- a/pmxcfs.adoc
+++ b/pmxcfs.adoc
@@ -1,18 +1,40 @@
-Proxmox Cluster file system (pmxcfs)
+[[chapter_pmxcfs]]
+ifdef::manvolnum[]
+pmxcfs(8)
+=========
+:pve-toplevel:
+
+NAME
+----
+
+pmxcfs - Proxmox Cluster File System
+
+SYNOPSIS
+--------
+
+include::pmxcfs.8-synopsis.adoc[]
+
+DESCRIPTION
+-----------
+endif::manvolnum[]
+
+ifndef::manvolnum[]
+Proxmox Cluster File System (pmxcfs)

 ====================================
 ====================================

+:pve-toplevel:
+endif::manvolnum[]

 
 

-The Proxmox Cluster file system (pmxcfs) is a database-driven file
+The Proxmox Cluster file system (``pmxcfs'') is a database-driven file

 system for storing configuration files, replicated in real time to all
 system for storing configuration files, replicated in real time to all

-cluster nodes using corosync. We use this to store all PVE related
+cluster nodes using `corosync`. We use this to store all PVE related

 configuration files.
 
 Although the file system stores all data inside a persistent database
 on disk, a copy of the data resides in RAM. That imposes restriction
 configuration files.
 
 Although the file system stores all data inside a persistent database
 on disk, a copy of the data resides in RAM. That imposes restriction

-on the maximal size, which is currently 30MB. This is still enough to
+on the maximum size, which is currently 30MB. This is still enough to

 store the configuration of several thousand virtual machines.
 
 store the configuration of several thousand virtual machines.
 

-Advantages
-----------
+This system provides the following advantages:

 
 * seamless replication of all configuration to all nodes in real time
 * provides strong consistency checks to avoid duplicate VM IDs
 
 * seamless replication of all configuration to all nodes in real time
 * provides strong consistency checks to avoid duplicate VM IDs


@@ -20,8 +42,9 @@ Advantages
 * automatic updates of the corosync cluster configuration to all nodes
 * includes a distributed locking mechanism
 
 * automatic updates of the corosync cluster configuration to all nodes
 * includes a distributed locking mechanism
 

+

 POSIX Compatibility
 POSIX Compatibility

-~~~~~~~~~~~~~~~~~~~
+-------------------

 
 The file system is based on FUSE, so the behavior is POSIX like. But
 some feature are simply not implemented, because we do not need them:
 
 The file system is based on FUSE, so the behavior is POSIX like. But
 some feature are simply not implemented, because we do not need them:


@@ -39,11 +62,11 @@ some feature are simply not implemented, because we do not need them:
 * `O_TRUNC` creates are not atomic (FUSE restriction)
 
 
 * `O_TRUNC` creates are not atomic (FUSE restriction)
 
 

-File access rights
-~~~~~~~~~~~~~~~~~~
+File Access Rights
+------------------

 
 

-All files and directories are owned by user 'root' and have group
-'www-data'. Only root has write permissions, but group 'www-data' can
+All files and directories are owned by user `root` and have group
+`www-data`. Only root has write permissions, but group `www-data` can

 read most files. Files below the following paths:
 
  /etc/pve/priv/
 read most files. Files below the following paths:
 
  /etc/pve/priv/


@@ -51,15 +74,16 @@ read most files. Files below the following paths:
 
 are only accessible by root.
 
 
 are only accessible by root.
 

+

 Technology
 ----------
 
 We use the http://www.corosync.org[Corosync Cluster Engine] for
 cluster communication, and http://www.sqlite.org[SQlite] for the
 Technology
 ----------
 
 We use the http://www.corosync.org[Corosync Cluster Engine] for
 cluster communication, and http://www.sqlite.org[SQlite] for the

-database file. The filesystem is implemented in user space using
+database file. The file system is implemented in user space using

 http://fuse.sourceforge.net[FUSE].
 
 http://fuse.sourceforge.net[FUSE].
 

-File system layout
+File System Layout

 ------------------
 
 The file system is mounted at:
 ------------------
 
 The file system is mounted at:


@@ -71,59 +95,63 @@ Files
 
 [width="100%",cols="m,d"]
 |=======
 
 [width="100%",cols="m,d"]
 |=======

-|corosync.conf  |corosync cluster configuration file (previous to {pve} 4.x this file was called cluster.conf)
-|storage.cfg   |{pve} storage configuration
-|datacenter.cfg   |{pve} datacenter wide configuration (keyboard layout, proxy, ...)
-|user.cfg      |{pve} access control configuration (users/groups/...)
-|domains.cfg   |{pve} Authentication domains 
-|authkey.pub   | public key used by ticket system
-|pve-root-ca.pem | public certificate of cluster CA
-|priv/shadow.cfg  | shadow password file
-|priv/authkey.key | private key used by ticket system
-|priv/pve-root-ca.key | private key of cluster CA
-|nodes/<NAME>/pve-ssl.pem                 | public ssl certificate for web server (signed by cluster CA)
-|nodes/<NAME>/pve-ssl.key            | private ssl key for pve-ssl.pem
-|nodes/<NAME>/pveproxy-ssl.pem       | public ssl certificate (chain) for web server (optional override for pve-ssl.pem)
-|nodes/<NAME>/pveproxy-ssl.key       | private ssl key for pveproxy-ssl.pem (optional)
-|nodes/<NAME>/qemu-server/<VMID>.conf    | VM configuration data for KVM VMs
-|nodes/<NAME>/lxc/<VMID>.conf         | VM configuration data for LXC containers
-|firewall/cluster.fw | Firewall config applied to all nodes
-|firewall/<NAME>.fw  | Firewall config for individual nodes
-|firewall/<VMID>.fw  | Firewall config for VMs and Containers
+|`corosync.conf`                        | Corosync cluster configuration file (previous to {pve} 4.x this file was called cluster.conf)
+|`storage.cfg`                          | {pve} storage configuration
+|`datacenter.cfg`                       | {pve} datacenter wide configuration (keyboard layout, proxy, ...)
+|`user.cfg`                             | {pve} access control configuration (users/groups/...)
+|`domains.cfg`                          | {pve} authentication domains
+|`status.cfg`                           | {pve} external metrics server configuration
+|`authkey.pub`                          | Public key used by ticket system
+|`pve-root-ca.pem`                      | Public certificate of cluster CA
+|`priv/shadow.cfg`                      | Shadow password file
+|`priv/authkey.key`                     | Private key used by ticket system
+|`priv/pve-root-ca.key`                 | Private key of cluster CA
+|`nodes/<NAME>/pve-ssl.pem`             | Public SSL certificate for web server (signed by cluster CA)
+|`nodes/<NAME>/pve-ssl.key`             | Private SSL key for `pve-ssl.pem`
+|`nodes/<NAME>/pveproxy-ssl.pem`        | Public SSL certificate (chain) for web server (optional override for `pve-ssl.pem`)
+|`nodes/<NAME>/pveproxy-ssl.key`        | Private SSL key for `pveproxy-ssl.pem` (optional)
+|`nodes/<NAME>/qemu-server/<VMID>.conf` | VM configuration data for KVM VMs
+|`nodes/<NAME>/lxc/<VMID>.conf`         | VM configuration data for LXC containers
+|`firewall/cluster.fw`                  | Firewall configuration applied to all nodes
+|`firewall/<NAME>.fw`                   | Firewall configuration for individual nodes
+|`firewall/<VMID>.fw`                   | Firewall configuration for VMs and Containers

 |=======
 
 |=======
 

+

 Symbolic links
 ~~~~~~~~~~~~~~
 
 [width="100%",cols="m,m"]
 |=======
 Symbolic links
 ~~~~~~~~~~~~~~
 
 [width="100%",cols="m,m"]
 |=======

-|local         |nodes/<LOCAL_HOST_NAME>
-|qemu-server   |nodes/<LOCAL_HOST_NAME>/qemu-server/
-|lxc           |nodes/<LOCAL_HOST_NAME>/lxc/
+|`local`         | `nodes/<LOCAL_HOST_NAME>`
+|`qemu-server`   | `nodes/<LOCAL_HOST_NAME>/qemu-server/`
+|`lxc`           | `nodes/<LOCAL_HOST_NAME>/lxc/`

 |=======
 
 |=======
 

+

 Special status files for debugging (JSON)
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 [width="100%",cols="m,d"]
 |=======
 Special status files for debugging (JSON)
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 [width="100%",cols="m,d"]
 |=======

-| .version    |file versions (to detect file modifications)
-| .members    |Info about cluster members
-| .vmlist     |List of all VMs
-| .clusterlog |Cluster log (last 50 entries)
-| .rrd        |RRD data (most recent entries)
+|`.version`    |File versions (to detect file modifications)
+|`.members`    |Info about cluster members
+|`.vmlist`     |List of all VMs
+|`.clusterlog` |Cluster log (last 50 entries)
+|`.rrd`        |RRD data (most recent entries)

 |=======
 
 |=======
 

+

 Enable/Disable debugging
 ~~~~~~~~~~~~~~~~~~~~~~~~
 
 You can enable verbose syslog messages with:
 
 Enable/Disable debugging
 ~~~~~~~~~~~~~~~~~~~~~~~~
 
 You can enable verbose syslog messages with:
 

- echo "1" >/etc/pve/.debug 
+ echo "1" >/etc/pve/.debug

 
 And disable verbose syslog messages with:
 
 
 And disable verbose syslog messages with:
 

- echo "0" >/etc/pve/.debug 
+ echo "0" >/etc/pve/.debug

 
 
 Recovery
 
 
 Recovery


@@ -131,13 +159,14 @@ Recovery
 
 If you have major problems with your Proxmox VE host, e.g. hardware
 issues, it could be helpful to just copy the pmxcfs database file
 
 If you have major problems with your Proxmox VE host, e.g. hardware
 issues, it could be helpful to just copy the pmxcfs database file

-/var/lib/pve-cluster/config.db and move it to a new Proxmox VE
+`/var/lib/pve-cluster/config.db` and move it to a new Proxmox VE

 host. On the new host (with nothing running), you need to stop the
 host. On the new host (with nothing running), you need to stop the

-pve-cluster service and replace the config.db file (needed permissions
-0600). Second, adapt '/etc/hostname' and '/etc/hosts' according to the
-lost Proxmox VE host, then reboot and check. (And don´t forget your
+`pve-cluster` service and replace the `config.db` file (needed permissions
+`0600`). Second, adapt `/etc/hostname` and `/etc/hosts` according to the
+lost Proxmox VE host, then reboot and check. (And don't forget your

 VM/CT data)
 
 VM/CT data)
 

+

 Remove Cluster configuration
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 Remove Cluster configuration
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 


@@ -145,31 +174,49 @@ The recommended way is to reinstall the node after you removed it from
 your cluster. This makes sure that all secret cluster/ssh keys and any
 shared configuration data is destroyed.
 
 your cluster. This makes sure that all secret cluster/ssh keys and any
 shared configuration data is destroyed.
 

-In some cases, you might prefer to put a node back to local mode
-without reinstall, which is described here:
-
-* stop the cluster file system in '/etc/pve/'
+In some cases, you might prefer to put a node back to local mode without
+reinstall, which is described in
+<<pvecm_separate_node_without_reinstall,Separate A Node Without Reinstalling>>

 
 

- # systemctl stop pve-cluster

 
 

-* start it again but forcing local mode
+Recovering/Moving Guests from Failed Nodes
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

 
 

- # pmxcfs -l
+For the guest configuration files in `nodes/<NAME>/qemu-server/` (VMs) and
+`nodes/<NAME>/lxc/` (containers), {pve} sees the containing node `<NAME>` as
+owner of the respective guest. This concept enables the usage of local locks
+instead of expensive cluster-wide locks for preventing concurrent guest
+configuration changes.

 
 

-* remove the cluster config
+As a consequence, if the owning node of a guest fails (e.g., because of a power
+outage, fencing event, ..), a regular migration is not possible (even if all
+the disks are located on shared storage) because such a local lock on the
+(dead) owning node is unobtainable. This is not a problem for HA-managed
+guests, as {pve}'s High Availability stack includes the necessary
+(cluster-wide) locking and watchdog functionality to ensure correct and
+automatic recovery of guests from fenced nodes.

 
 

- # rm /etc/pve/cluster.conf
- # rm /etc/cluster/cluster.conf
- # rm /var/lib/pve-cluster/corosync.authkey
+If a non-HA-managed guest has only shared disks (and no other local resources
+which are only available on the failed node are configured), a manual recovery
+is possible by simply moving the guest configuration file from the failed
+node's directory in `/etc/pve/` to an alive node's directory (which changes the
+logical owner or location of the guest).

 
 

-* stop the cluster file system again
+For example, recovering the VM with ID `100` from a dead `node1` to another
+node `node2` works with the following command executed when logged in as root
+on any member node of the cluster:

 
 

- # service pve-cluster stop
+ mv /etc/pve/nodes/node1/qemu-server/100.conf /etc/pve/nodes/node2/

 
 

-* restart pve services (or reboot)
+WARNING: Before manually recovering a guest like this, make absolutely sure
+that the failed source node is really powered off/fenced. Otherwise {pve}'s
+locking principles are violated by the `mv` command, which can have unexpected
+consequences.

 
 

- # service pve-cluster start
- # service pvedaemon restart
- # service pveproxy restart
- # service pvestatd restart
+WARNING: Guest with local disks (or other local resources which are only
+available on the dead node) are not recoverable like this. Either wait for the
+failed node to rejoin the cluster or restore such guests from backups.

 
 

+ifdef::manvolnum[]
+include::pve-copyright.adoc[]
+endif::manvolnum[]