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2 | a8083063 | Iustin Pop | #
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3 | a8083063 | Iustin Pop | |
4 | a8083063 | Iustin Pop | # Copyright (C) 2006, 2007 Google Inc.
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5 | a8083063 | Iustin Pop | #
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6 | a8083063 | Iustin Pop | # This program is free software; you can redistribute it and/or modify
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7 | a8083063 | Iustin Pop | # it under the terms of the GNU General Public License as published by
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8 | a8083063 | Iustin Pop | # the Free Software Foundation; either version 2 of the License, or
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9 | a8083063 | Iustin Pop | # (at your option) any later version.
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10 | a8083063 | Iustin Pop | #
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11 | a8083063 | Iustin Pop | # This program is distributed in the hope that it will be useful, but
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12 | a8083063 | Iustin Pop | # WITHOUT ANY WARRANTY; without even the implied warranty of
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13 | a8083063 | Iustin Pop | # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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14 | a8083063 | Iustin Pop | # General Public License for more details.
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15 | a8083063 | Iustin Pop | #
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16 | a8083063 | Iustin Pop | # You should have received a copy of the GNU General Public License
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17 | a8083063 | Iustin Pop | # along with this program; if not, write to the Free Software
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18 | a8083063 | Iustin Pop | # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
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19 | a8083063 | Iustin Pop | # 02110-1301, USA.
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20 | a8083063 | Iustin Pop | |
21 | a8083063 | Iustin Pop | |
22 | a8083063 | Iustin Pop | """Module encapsulating ssh functionality.
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23 | a8083063 | Iustin Pop |
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24 | a8083063 | Iustin Pop | """
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25 | a8083063 | Iustin Pop | |
26 | a8083063 | Iustin Pop | |
27 | a8083063 | Iustin Pop | import os |
28 | a8083063 | Iustin Pop | |
29 | a8083063 | Iustin Pop | from ganeti import logger |
30 | a8083063 | Iustin Pop | from ganeti import utils |
31 | a8083063 | Iustin Pop | from ganeti import errors |
32 | 82122173 | Iustin Pop | from ganeti import constants |
33 | 82122173 | Iustin Pop | |
34 | 82122173 | Iustin Pop | |
35 | 82122173 | Iustin Pop | __all__ = ["SSHCall", "CopyFileToNode", "VerifyNodeHostname", |
36 | 82122173 | Iustin Pop | "KNOWN_HOSTS_OPTS", "BATCH_MODE_OPTS", "ASK_KEY_OPTS"] |
37 | 82122173 | Iustin Pop | |
38 | 82122173 | Iustin Pop | |
39 | 82122173 | Iustin Pop | KNOWN_HOSTS_OPTS = [ |
40 | 82122173 | Iustin Pop | "-oGlobalKnownHostsFile=%s" % constants.SSH_KNOWN_HOSTS_FILE,
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41 | 82122173 | Iustin Pop | "-oUserKnownHostsFile=/dev/null",
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42 | 82122173 | Iustin Pop | ] |
43 | 82122173 | Iustin Pop | |
44 | 82122173 | Iustin Pop | # Note: BATCH_MODE conflicts with ASK_KEY
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45 | 82122173 | Iustin Pop | BATCH_MODE_OPTS = [ |
46 | 82122173 | Iustin Pop | "-oEscapeChar=none",
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47 | 82122173 | Iustin Pop | "-oBatchMode=yes",
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48 | 82122173 | Iustin Pop | "-oStrictHostKeyChecking=yes",
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49 | 82122173 | Iustin Pop | ] |
50 | 82122173 | Iustin Pop | |
51 | 82122173 | Iustin Pop | ASK_KEY_OPTS = [ |
52 | 82122173 | Iustin Pop | "-oStrictHostKeyChecking=ask",
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53 | 82122173 | Iustin Pop | "-oEscapeChar=none",
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54 | 82122173 | Iustin Pop | "-oHashKnownHosts=no",
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55 | 82122173 | Iustin Pop | ] |
56 | 82122173 | Iustin Pop | |
57 | 72f0f7fd | Iustin Pop | |
58 | 70d9e3d8 | Iustin Pop | def GetUserFiles(user, mkdir=False): |
59 | 70d9e3d8 | Iustin Pop | """Return the paths of a user's ssh files.
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60 | 70d9e3d8 | Iustin Pop |
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61 | 70d9e3d8 | Iustin Pop | The function will return a triplet (priv_key_path, pub_key_path,
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62 | 70d9e3d8 | Iustin Pop | auth_key_path) that are used for ssh authentication. Currently, the
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63 | 70d9e3d8 | Iustin Pop | keys used are DSA keys, so this function will return:
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64 | 70d9e3d8 | Iustin Pop | (~user/.ssh/id_dsa, ~user/.ssh/id_dsa.pub,
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65 | 70d9e3d8 | Iustin Pop | ~user/.ssh/authorized_keys).
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66 | 70d9e3d8 | Iustin Pop |
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67 | 70d9e3d8 | Iustin Pop | If the optional parameter mkdir is True, the ssh directory will be
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68 | 70d9e3d8 | Iustin Pop | created if it doesn't exist.
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69 | 70d9e3d8 | Iustin Pop |
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70 | 70d9e3d8 | Iustin Pop | Regardless of the mkdir parameters, the script will raise an error
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71 | 70d9e3d8 | Iustin Pop | if ~user/.ssh is not a directory.
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72 | 70d9e3d8 | Iustin Pop |
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73 | 70d9e3d8 | Iustin Pop | """
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74 | 70d9e3d8 | Iustin Pop | user_dir = utils.GetHomeDir(user) |
75 | 70d9e3d8 | Iustin Pop | if not user_dir: |
76 | 70d9e3d8 | Iustin Pop | raise errors.OpExecError("Cannot resolve home of user %s" % user) |
77 | 70d9e3d8 | Iustin Pop | |
78 | 70d9e3d8 | Iustin Pop | ssh_dir = os.path.join(user_dir, ".ssh")
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79 | 70d9e3d8 | Iustin Pop | if not os.path.lexists(ssh_dir): |
80 | 70d9e3d8 | Iustin Pop | if mkdir:
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81 | 70d9e3d8 | Iustin Pop | try:
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82 | 70d9e3d8 | Iustin Pop | os.mkdir(ssh_dir, 0700)
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83 | 70d9e3d8 | Iustin Pop | except EnvironmentError, err: |
84 | 70d9e3d8 | Iustin Pop | raise errors.OpExecError("Can't create .ssh dir for user %s: %s" % |
85 | 70d9e3d8 | Iustin Pop | (user, str(err)))
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86 | 70d9e3d8 | Iustin Pop | elif not os.path.isdir(ssh_dir): |
87 | 70d9e3d8 | Iustin Pop | raise errors.OpExecError("path ~%s/.ssh is not a directory" % user) |
88 | 70d9e3d8 | Iustin Pop | |
89 | 70d9e3d8 | Iustin Pop | return [os.path.join(ssh_dir, base)
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90 | 70d9e3d8 | Iustin Pop | for base in ["id_dsa", "id_dsa.pub", "authorized_keys"]] |
91 | 70d9e3d8 | Iustin Pop | |
92 | 70d9e3d8 | Iustin Pop | |
93 | 00003458 | Guido Trotter | def BuildSSHCmd(hostname, user, command, batch=True, ask_key=False): |
94 | 00003458 | Guido Trotter | """Build an ssh string to execute a command on a remote node.
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95 | a8083063 | Iustin Pop |
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96 | a8083063 | Iustin Pop | Args:
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97 | a8083063 | Iustin Pop | hostname: the target host, string
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98 | a8083063 | Iustin Pop | user: user to auth as
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99 | a8083063 | Iustin Pop | command: the command
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100 | 82122173 | Iustin Pop | batch: if true, ssh will run in batch mode with no prompting
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101 | 82122173 | Iustin Pop | ask_key: if true, ssh will run with StrictHostKeyChecking=ask, so that
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102 | 82122173 | Iustin Pop | we can connect to an unknown host (not valid in batch mode)
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103 | a8083063 | Iustin Pop |
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104 | a8083063 | Iustin Pop | Returns:
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105 | 00003458 | Guido Trotter | The ssh call to run 'command' on the remote host.
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106 | a8083063 | Iustin Pop |
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107 | a8083063 | Iustin Pop | """
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108 | 82122173 | Iustin Pop | argv = ["ssh", "-q"] |
109 | 82122173 | Iustin Pop | argv.extend(KNOWN_HOSTS_OPTS) |
110 | a8083063 | Iustin Pop | if batch:
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111 | a8083063 | Iustin Pop | # if we are in batch mode, we can't ask the key
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112 | a8083063 | Iustin Pop | if ask_key:
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113 | 3ecf6786 | Iustin Pop | raise errors.ProgrammerError("SSH call requested conflicting options") |
114 | 82122173 | Iustin Pop | argv.extend(BATCH_MODE_OPTS) |
115 | 82122173 | Iustin Pop | elif ask_key:
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116 | 82122173 | Iustin Pop | argv.extend(ASK_KEY_OPTS) |
117 | 72f0f7fd | Iustin Pop | argv.extend(["%s@%s" % (user, hostname), command])
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118 | 00003458 | Guido Trotter | return argv
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119 | 00003458 | Guido Trotter | |
120 | 00003458 | Guido Trotter | |
121 | 00003458 | Guido Trotter | def SSHCall(hostname, user, command, batch=True, ask_key=False): |
122 | 00003458 | Guido Trotter | """Execute a command on a remote node.
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123 | 00003458 | Guido Trotter |
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124 | 00003458 | Guido Trotter | This method has the same return value as `utils.RunCmd()`, which it
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125 | 00003458 | Guido Trotter | uses to launch ssh.
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126 | 00003458 | Guido Trotter |
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127 | 00003458 | Guido Trotter | Args:
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128 | 00003458 | Guido Trotter | hostname: the target host, string
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129 | 00003458 | Guido Trotter | user: user to auth as
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130 | 00003458 | Guido Trotter | command: the command
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131 | 00003458 | Guido Trotter | batch: if true, ssh will run in batch mode with no prompting
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132 | 00003458 | Guido Trotter | ask_key: if true, ssh will run with StrictHostKeyChecking=ask, so that
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133 | 00003458 | Guido Trotter | we can connect to an unknown host (not valid in batch mode)
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134 | 00003458 | Guido Trotter |
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135 | 00003458 | Guido Trotter | Returns:
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136 | 00003458 | Guido Trotter | `utils.RunResult` as for `utils.RunCmd()`
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137 | 00003458 | Guido Trotter |
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138 | 00003458 | Guido Trotter | """
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139 | 00003458 | Guido Trotter | return utils.RunCmd(BuildSSHCmd(hostname, user, command, batch=batch, ask_key=ask_key))
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140 | a8083063 | Iustin Pop | |
141 | a8083063 | Iustin Pop | |
142 | a8083063 | Iustin Pop | def CopyFileToNode(node, filename): |
143 | a8083063 | Iustin Pop | """Copy a file to another node with scp.
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144 | a8083063 | Iustin Pop |
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145 | a8083063 | Iustin Pop | Args:
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146 | a8083063 | Iustin Pop | node: node in the cluster
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147 | a8083063 | Iustin Pop | filename: absolute pathname of a local file
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148 | a8083063 | Iustin Pop |
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149 | a8083063 | Iustin Pop | Returns:
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150 | a8083063 | Iustin Pop | success: True/False
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151 | a8083063 | Iustin Pop |
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152 | a8083063 | Iustin Pop | """
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153 | a8083063 | Iustin Pop | if not os.path.isfile(filename): |
154 | a8083063 | Iustin Pop | logger.Error("file %s does not exist" % (filename))
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155 | a8083063 | Iustin Pop | return False |
156 | a8083063 | Iustin Pop | |
157 | a8083063 | Iustin Pop | if not os.path.isabs(filename): |
158 | a8083063 | Iustin Pop | logger.Error("file %s must be an absolute path" % (filename))
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159 | a8083063 | Iustin Pop | return False |
160 | a8083063 | Iustin Pop | |
161 | 82122173 | Iustin Pop | command = ["scp", "-q", "-p"] |
162 | 82122173 | Iustin Pop | command.extend(KNOWN_HOSTS_OPTS) |
163 | 82122173 | Iustin Pop | command.extend(BATCH_MODE_OPTS) |
164 | 82122173 | Iustin Pop | command.append(filename) |
165 | 82122173 | Iustin Pop | command.append("%s:%s" % (node, filename))
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166 | a8083063 | Iustin Pop | |
167 | a8083063 | Iustin Pop | result = utils.RunCmd(command) |
168 | a8083063 | Iustin Pop | |
169 | a8083063 | Iustin Pop | if result.failed:
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170 | a8083063 | Iustin Pop | logger.Error("copy to node %s failed (%s) error %s,"
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171 | a8083063 | Iustin Pop | " command was %s" %
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172 | a8083063 | Iustin Pop | (node, result.fail_reason, result.output, result.cmd)) |
173 | a8083063 | Iustin Pop | |
174 | a8083063 | Iustin Pop | return not result.failed |
175 | a8083063 | Iustin Pop | |
176 | a8083063 | Iustin Pop | |
177 | a8083063 | Iustin Pop | def VerifyNodeHostname(node): |
178 | a8083063 | Iustin Pop | """Verify hostname consistency via SSH.
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179 | a8083063 | Iustin Pop |
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180 | a8083063 | Iustin Pop |
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181 | a8083063 | Iustin Pop | This functions connects via ssh to a node and compares the hostname
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182 | a8083063 | Iustin Pop | reported by the node to the name with have (the one that we
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183 | a8083063 | Iustin Pop | connected to).
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184 | a8083063 | Iustin Pop |
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185 | a8083063 | Iustin Pop | This is used to detect problems in ssh known_hosts files
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186 | a8083063 | Iustin Pop | (conflicting known hosts) and incosistencies between dns/hosts
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187 | a8083063 | Iustin Pop | entries and local machine names
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188 | a8083063 | Iustin Pop |
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189 | a8083063 | Iustin Pop | Args:
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190 | a8083063 | Iustin Pop | node: nodename of a host to check. can be short or full qualified hostname
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191 | a8083063 | Iustin Pop |
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192 | a8083063 | Iustin Pop | Returns:
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193 | a8083063 | Iustin Pop | (success, detail)
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194 | a8083063 | Iustin Pop | where
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195 | a8083063 | Iustin Pop | success: True/False
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196 | a8083063 | Iustin Pop | detail: String with details
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197 | a8083063 | Iustin Pop |
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198 | a8083063 | Iustin Pop | """
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199 | a8083063 | Iustin Pop | retval = SSHCall(node, 'root', 'hostname') |
200 | a8083063 | Iustin Pop | |
201 | a8083063 | Iustin Pop | if retval.failed:
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202 | a8083063 | Iustin Pop | msg = "ssh problem"
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203 | a8083063 | Iustin Pop | output = retval.output |
204 | a8083063 | Iustin Pop | if output:
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205 | a8083063 | Iustin Pop | msg += ": %s" % output
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206 | a8083063 | Iustin Pop | return False, msg |
207 | a8083063 | Iustin Pop | |
208 | a8083063 | Iustin Pop | remotehostname = retval.stdout.strip() |
209 | a8083063 | Iustin Pop | |
210 | a8083063 | Iustin Pop | if not remotehostname or remotehostname != node: |
211 | a8083063 | Iustin Pop | return False, "hostname mismatch, got %s" % remotehostname |
212 | a8083063 | Iustin Pop | |
213 | a8083063 | Iustin Pop | return True, "host matches" |