4 # Copyright (C) 2006, 2007 Google Inc.
6 # This program is free software; you can redistribute it and/or modify
7 # it under the terms of the GNU General Public License as published by
8 # the Free Software Foundation; either version 2 of the License, or
9 # (at your option) any later version.
11 # This program is distributed in the hope that it will be useful, but
12 # WITHOUT ANY WARRANTY; without even the implied warranty of
13 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 # General Public License for more details.
16 # You should have received a copy of the GNU General Public License
17 # along with this program; if not, write to the Free Software
18 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
22 """Global Configuration data for Ganeti.
24 This module provides the interface to a special case of cluster
25 configuration data, which is mostly static and available to all nodes.
32 from ganeti import errors
33 from ganeti import constants
34 from ganeti import utils
38 """Interface to static cluster data.
40 This is different that the config.ConfigWriter class in that it
41 holds data that is (mostly) constant after the cluster
42 initialization. Its purpose is to allow limited customization of
43 things which would otherwise normally live in constants.py. Note
44 that this data cannot live in ConfigWriter as that is available only
45 on the master node, and our data must be readable by both the master
48 Other particularities of the datastore:
49 - keys are restricted to predefined values
50 - values are small (<4k)
51 - some keys are handled specially (read from the system)
54 _SS_FILEPREFIX = "ssconf_"
55 SS_HYPERVISOR = "hypervisor"
56 SS_NODED_PASS = "node_pass"
57 SS_MASTER_NODE = "master_node"
58 SS_MASTER_IP = "master_ip"
59 SS_MASTER_NETDEV = "master_netdev"
60 SS_CLUSTER_NAME = "cluster_name"
61 SS_FILE_STORAGE_DIR = "file_storage_dir"
62 SS_CONFIG_VERSION = "config_version"
63 _VALID_KEYS = (SS_HYPERVISOR, SS_NODED_PASS, SS_MASTER_NODE, SS_MASTER_IP,
64 SS_MASTER_NETDEV, SS_CLUSTER_NAME, SS_FILE_STORAGE_DIR,
68 def __init__(self, cfg_location=None):
69 if cfg_location is None:
70 self._cfg_dir = constants.DATA_DIR
72 self._cfg_dir = cfg_location
74 def KeyToFilename(self, key):
75 """Convert a given key into filename.
78 if key not in self._VALID_KEYS:
79 raise errors.ProgrammerError("Invalid key requested from SSConf: '%s'"
82 filename = self._cfg_dir + '/' + self._SS_FILEPREFIX + key
85 def _ReadFile(self, key):
86 """Generic routine to read keys.
88 This will read the file which holds the value requested. Errors
89 will be changed into ConfigurationErrors.
92 filename = self.KeyToFilename(key)
94 fh = file(filename, 'r')
96 data = fh.readline(self._MAX_SIZE)
97 data = data.rstrip('\n')
100 except EnvironmentError, err:
101 raise errors.ConfigurationError("Can't read from the ssconf file:"
105 def GetNodeDaemonPort(self):
106 """Get the node daemon port for this cluster.
108 Note that this routine does not read a ganeti-specific file, but
109 instead uses socket.getservbyname to allow pre-customization of
110 this parameter outside of ganeti.
114 port = socket.getservbyname("ganeti-noded", "tcp")
116 port = constants.DEFAULT_NODED_PORT
120 def GetHypervisorType(self):
121 """Get the hypervisor type for this cluster.
124 return self._ReadFile(self.SS_HYPERVISOR)
126 def GetNodeDaemonPassword(self):
127 """Get the node password for this cluster.
130 return self._ReadFile(self.SS_NODED_PASS)
132 def GetMasterNode(self):
133 """Get the hostname of the master node for this cluster.
136 return self._ReadFile(self.SS_MASTER_NODE)
138 def GetMasterIP(self):
139 """Get the IP of the master node for this cluster.
142 return self._ReadFile(self.SS_MASTER_IP)
144 def GetMasterNetdev(self):
145 """Get the netdev to which we'll add the master ip.
148 return self._ReadFile(self.SS_MASTER_NETDEV)
150 def GetClusterName(self):
151 """Get the cluster name.
154 return self._ReadFile(self.SS_CLUSTER_NAME)
156 def GetFileStorageDir(self):
157 """Get the file storage dir.
160 return self._ReadFile(self.SS_FILE_STORAGE_DIR)
162 def GetConfigVersion(self):
163 """Get the configuration version.
166 value = self._ReadFile(self.SS_CONFIG_VERSION)
169 except (ValueError, TypeError), err:
170 raise errors.ConfigurationError("Failed to convert config version %s to"
171 " int: '%s'" % (value, str(err)))
173 def GetFileList(self):
174 """Return the list of all config files.
176 This is used for computing node replication data.
179 return [self.KeyToFilename(key) for key in self._VALID_KEYS]
182 class WritableSimpleStore(SimpleStore):
183 """This is a read/write interface to SimpleStore, which is used rarely, when
184 values need to be changed. Since WriteFile handles updates in an atomic way
185 it should be fine to use two WritableSimpleStore at the same time, but in
186 the future we might want to put additional protection for this class.
188 A WritableSimpleStore cannot be used to update system-dependent values.
192 def SetKey(self, key, value):
193 """Set the value of a key.
195 This should be used only when adding a node to a cluster, or in other
196 infrequent operations such as cluster-rename or master-failover.
199 file_name = self.KeyToFilename(key)
200 utils.WriteFile(file_name, data="%s\n" % str(value),
201 uid=0, gid=0, mode=0400)
204 def GetMasterAndMyself(ss=None):
205 """Get the master node and my own hostname.
207 This can be either used for a 'soft' check (compared to CheckMaster,
208 which exits) or just for computing both at the same time.
210 The function does not handle any errors, these should be handled in
211 the caller (errors.ConfigurationError, errors.ResolverError).
216 return ss.GetMasterNode(), utils.HostInfo().name
218 def CheckMaster(debug, ss=None):
219 """Checks the node setup.
221 If this is the master, the function will return. Otherwise it will
222 exit with an exit code based on the node status.
226 master_name, myself = GetMasterAndMyself(ss)
227 except errors.ConfigurationError, err:
228 print "Cluster configuration incomplete: '%s'" % str(err)
229 sys.exit(constants.EXIT_NODESETUP_ERROR)
230 except errors.ResolverError, err:
231 sys.stderr.write("Cannot resolve my own name (%s)\n" % err.args[0])
232 sys.exit(constants.EXIT_NODESETUP_ERROR)
234 if myself != master_name:
236 sys.stderr.write("Not master, exiting.\n")
237 sys.exit(constants.EXIT_NOTMASTER)