1REPAIR(1) REPAIR(1)
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6 repair - Repair conflicts in the Coda Distributed File System
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9 repair -d
10 repair -allowclear
13 repair object_in_conflict fixfile [ repair_options ]
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19 The Coda repair tool allows you to manually resolve two kinds of con‐
20 flicts resulted from partitioned updates. Server-server conflicts are
21 conflicting mutations performed on partitioned servers that can not be
22 automatically resolved. Local-global conflicts are caused by mutations
23 performed on a disconnected client that are in conflict with the global
24 server state.
25 To use the repair tool interactively, type repair at the command
27 prompt.
28 Server-Server conflicts can be repaired from the command line without
30 entering interactive mode. This is useful if you need to repair many
31 conflicts within a volume at a time and wish to write a shell script.
32 Please see the EXAMPLES section for examples on invoking complete
33 repair sequences from the command line.
34 A description of the repair commands follows:
36 beginrepair object
38 verifies that object is indeed in conflict. It will print out
39 messages to indicate whether the current repair session is for
40 server-server conflict or local-global conflict.
41 For a server-server repair session, this command locks the cor‐
43 responding volume and and mounts its individual replicas read-
44 only. It will inform the users to only use the comparedirs,
45 dorepair and removeinc commands to repair the conflict.
46 For a local-global repair session, both local and global repli‐
48 cas of object are visible at object/local (read-only) and
49 object/global (mutable and serving as the workspace for storing
50 the repair result for object). You need to iterate through the
51 current sessions local-mutations-list containing all the local
52 updates to object and its descendants. Each operation in local-
53 mutations-list must be accounted for and Venus maintains the
54 current-mutation being iterated. Use the checklocal command to
55 find out the conflict between the current-mutation and the
56 server state. Note that not all local mutations are necessarily
57 in conflict, and you can use the listlocal command to see all
58 the operations in local-mutations-list. You can advance the
59 iteration to the next operation using either the preservelocal
60 or the discardlocal command with the former replaying the cur‐
61 rent-mutation operation on the relevant global replicas. To
62 speed up the iteration, the preservealllocal command repeats
63 preservelocal until the local-mutations-list is exhausted or the
64 first replay failure. Similarly, the discardalllocal command
65 repeats discardlocal until exhausting the local-mutations-list.
66 You can use external tools such as emacs(1) to make direct
67 updates on needed replicas under object/global. Use the quit
68 command to either commit or abort the session.
69 quit If the current session is repairing a server-server conflict,
71 this command releases all the volume-level locks and causes the
72 repair tool to return to the shell. If the current session is
73 repairing a local-global conflict, this command asks you whether
74 to commit or abort the repair session. If you answer yes, the
75 mutations performed on the relevant global replicas will be com‐
76 mitted to the servers. Otherwise, the repair result will be
77 aborted as if this repair session has never happened.
78 help Prints out a help message.
80 Use the following commands to repair a server-server conflict:
82 comparedirs object fixfile [ -acl user rwlidka ] [ -mode newmode ] [
84 -owner username ]
85 Compares the mounted read-only replicas of a directory in con‐
86 flict and prints the repair commands in fixfile to make the
87 replicas identical. To print out the repair commands on your
88 terminal give stdout as the pathname for fixfile. Compensating
89 actions for Name/Name conflicts and Update/Update conflicts are
90 not given. The user is only told about their existence and
91 required to edit the fixfile manually. You should have already
92 done a beginrepair on object and this command works only if
93 object is a directory.
94 dorepair object fixfile
96 Does the actual repair of an object. If the repair succeeds,
97 each accessible replica will be marked consistent. You will be
98 prompted for the arguments if they are missing, and will be
99 asked to confirm the repair. You should have already done a
100 beginrepair on this object (or on on some other object in this
101 volume.). If object is a file or symbolic link, fixfile must
102 provide its new contents. If object is a directory, fixfile
103 must provide a sequence of directory repair commands for each
104 replica. The format of fixfile for directories is as follows:
105 replica <servername> <id of replica1>
107 <repair commands for replica1>
108 replica <servername> <id of replica2>
109 <repair commands for replica2>
110 and so on
111 Repair commands are given one per line. Blank lines are ok. id
113 of replica1, id of replica2, etc. are numbers that identify
114 each replica. These are the same as the volume ids of read-
115 write volumes corresponding to a replicated volume. The volume
116 ids can be obtained by doing an ls on the inconsistent object,
117 after the beginrepair command has succeeded. The directory
118 repair commands are:
119 createf <filename> <fid.0> <fid.1> <fid.2>
121 creates <symlinkname> <fid.0> <fid.1> <fid.2>
122 createl <linkname> <fid.0> <fid.1> <fid.2>
123 created <dirname> <fid.0> <fid.1> <fid.2>
124 removefsl <filename or symlinkname or linkname>
125 removed <dirname>
126 mv <srcname> <tgtname>
127 <src <fid.0> <fid.1> <fid.2>>
128 <target <fid.1> <fid.2>>
129 setacl <username> [rwlikda]
130 delacl <username>
131 setmode <newmode>
132 setowner <new owner name>
133 setmtime <new modified time>
134 Note that for the setacl command, the short form access rights
136 of all and none can also be used.
137 removeinc object
139 Removes the inconsistent object if it is file or a symbolic
140 link. If the object is a directory, all the descendants of the
141 object will be removed in all the accessible replicas and the
142 directory itself will be removed as long as its replicas are
143 identical. If the owner or the ACL of the directory replicas are
144 different, you have to repair the conflict first.
145 clearinc object
147 Compares the mounted read only replicas of a directory in con‐
148 flict and if the replicas are identical it clears the inconsis‐
149 tency flag of the replicas. Otherwise it will inform you about
150 the inequality of the replicas. You should run the comparedirs
151 command to find out the cause of conflict. This command should
152 be used only for directories. Files and symbolic links are
153 cleared of their inconsistency with the dorepair command.
154 The following commands are used only for repairing local-global con‐
156 flicts:
157 checklocal
159 Checks to see if the current-mutation being iterated by the cur‐
160 rent local-global repair session is in conflict with the server
161 state. It displays the operator and operand (s) of the current-
162 mutation operation and indicates whether it is in conflict with
163 the relevant server replicas. If it is in conflict, a brief rea‐
164 son of the conflict is given. Note that this command does not
165 advance the iteration of the local-mutations-list.
166 discardlocal
168 Simply advances the iteration of the local-mutations-list of the
169 current local-global repair session to the next operation. Use
170 this command when the user does not want the current-mutation
171 operation to have any effect on the repair result.
172 preservelocal
174 Tries to replay the current-mutation of the current local-global
175 repair session on the relevant global replicas. In other words,
176 it will try to preserve the effect of the current mutation in
177 the repair result. If the replay succeeds, the iteration of
178 local-mutations-list will be advanced to the next operation. The
179 effect of the replay is visible only on this client and not on
180 the server until the repair result is successfully committed. If
181 the replay fails, information about the reason of the failure
182 will be displayed.
183 discardalllocal
185 Repeatedly performs the discardlocal command until the local-
186 mutations-list is exhausted. Its effect is to finish the itera‐
187 tion and discard the effect of all the remaining mutations on
188 the repair result.
189 preservealllocal
191 Repeatedly performs the preservelocal command until the first
192 failure or the iteration of local-mutations-list is exhausted.
193 This command is used if the user wants to preserve the effect of
194 all the remaining mutation operations in the repair result.
195 listlocal
197 Prints out all the mutation operations in the local-mutations-
198 list of the current local-global repair session.
199 The following commands existed in old versions but are no longer sup‐
201 ported:
202 showreplicas object
204 Shows the names of the individual replicas of object, and the
205 pathnames by which these replicas may be examined read-only. A
206 beginrepair must have been done earlier on this object (or on
207 another object in the same volume).
208 unlockvolume pathname
210 Tells Venus to unlock the specified volume in repair. No
211 check is done to see if you locked the volume during this
212 repair session. The primary use of this command is to unlock
213 volumes that were locked during a previous, aborted, invocation
214 of the repair tool. The command will fail if Venus discovers
215 that you do not hold the repair lock on the server. This could
216 happen, for example, if your aborted repair occurred on another
217 workstation, or if you were not repairing the volume in the
218 first place.
219
221 This will cause repair to examine the object "common", generate a fix
222 file for it and in addition to the contents of the fix file, and set
223 the acl for hmpierce to rlidwka on the replica.
224 repair common /tmp/fix -acl hmpierce all
226 The same repair would look like this in interactive mode:
228 repair> beginrepair common
230 repair> comparedirs common /tmp/fix -acl hmpierce all
231 repair> dorepair common /tmp/fix
232 repair> endrepair
233 repair> quit
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236 · M. Satyanarayanan, 1989, Created
237 · Puneet Kumar, 1991, Substantially revised
239 · Joshua Raiff, 1993, Created man page
241 · Qi Lu, 1995, Added local-global repair commands and revised man page
243 · Henry M. Pierce, 1998, updated for command line options
245Coda Distributed File System 25 April 2005 REPAIR(1)