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19 package org.apache.hadoop.hbase.master.handler;
20
21 import java.io.IOException;
22 import java.util.ArrayList;
23 import java.util.List;
24 import java.util.Map;
25 import java.util.NavigableMap;
26
27 import org.apache.commons.logging.Log;
28 import org.apache.commons.logging.LogFactory;
29 import org.apache.hadoop.classification.InterfaceAudience;
30 import org.apache.hadoop.hbase.HRegionInfo;
31 import org.apache.hadoop.hbase.Server;
32 import org.apache.hadoop.hbase.ServerName;
33 import org.apache.hadoop.hbase.catalog.CatalogTracker;
34 import org.apache.hadoop.hbase.catalog.MetaReader;
35 import org.apache.hadoop.hbase.client.Result;
36 import org.apache.hadoop.hbase.executor.EventHandler;
37 import org.apache.hadoop.hbase.executor.EventType;
38 import org.apache.hadoop.hbase.master.AssignmentManager;
39 import org.apache.hadoop.hbase.master.DeadServer;
40 import org.apache.hadoop.hbase.master.MasterServices;
41 import org.apache.hadoop.hbase.master.RegionState;
42 import org.apache.hadoop.hbase.master.RegionStates;
43 import org.apache.hadoop.hbase.master.ServerManager;
44 import org.apache.hadoop.hbase.zookeeper.ZKAssign;
45 import org.apache.zookeeper.KeeperException;
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51
52 @InterfaceAudience.Private
53 public class ServerShutdownHandler extends EventHandler {
54 private static final Log LOG = LogFactory.getLog(ServerShutdownHandler.class);
55 protected final ServerName serverName;
56 protected final MasterServices services;
57 protected final DeadServer deadServers;
58 protected final boolean shouldSplitHlog;
59
60 public ServerShutdownHandler(final Server server, final MasterServices services,
61 final DeadServer deadServers, final ServerName serverName,
62 final boolean shouldSplitHlog) {
63 this(server, services, deadServers, serverName, EventType.M_SERVER_SHUTDOWN,
64 shouldSplitHlog);
65 }
66
67 ServerShutdownHandler(final Server server, final MasterServices services,
68 final DeadServer deadServers, final ServerName serverName, EventType type,
69 final boolean shouldSplitHlog) {
70 super(server, type);
71 this.serverName = serverName;
72 this.server = server;
73 this.services = services;
74 this.deadServers = deadServers;
75 if (!this.deadServers.isDeadServer(this.serverName)) {
76 LOG.warn(this.serverName + " is NOT in deadservers; it should be!");
77 }
78 this.shouldSplitHlog = shouldSplitHlog;
79 }
80
81 @Override
82 public String getInformativeName() {
83 if (serverName != null) {
84 return this.getClass().getSimpleName() + " for " + serverName;
85 } else {
86 return super.getInformativeName();
87 }
88 }
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93 boolean isCarryingMeta() {
94 return false;
95 }
96
97 @Override
98 public String toString() {
99 String name = "UnknownServerName";
100 if(server != null && server.getServerName() != null) {
101 name = server.getServerName().toString();
102 }
103 return getClass().getSimpleName() + "-" + name + "-" + getSeqid();
104 }
105
106 @Override
107 public void process() throws IOException {
108 final ServerName serverName = this.serverName;
109 try {
110 try {
111 if (this.shouldSplitHlog) {
112 LOG.info("Splitting logs for " + serverName);
113 this.services.getMasterFileSystem().splitLog(serverName);
114 } else {
115 LOG.info("Skipping log splitting for " + serverName);
116 }
117 } catch (IOException ioe) {
118
119
120 this.services.getExecutorService().submit((ServerShutdownHandler)this);
121 this.deadServers.add(serverName);
122 throw new IOException("failed log splitting for " +
123 serverName + ", will retry", ioe);
124 }
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146 if (isCarryingMeta()
147 || !services.getAssignmentManager().isFailoverCleanupDone()) {
148 this.services.getServerManager().processDeadServer(serverName);
149 return;
150 }
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167 NavigableMap<HRegionInfo, Result> hris = null;
168 while (!this.server.isStopped()) {
169 try {
170 this.server.getCatalogTracker().waitForMeta();
171 hris = MetaReader.getServerUserRegions(this.server.getCatalogTracker(),
172 this.serverName);
173 break;
174 } catch (InterruptedException e) {
175 Thread.currentThread().interrupt();
176 throw new IOException("Interrupted", e);
177 } catch (IOException ioe) {
178 LOG.info("Received exception accessing META during server shutdown of " +
179 serverName + ", retrying META read", ioe);
180 }
181 }
182 if (this.server.isStopped()) {
183 throw new IOException("Server is stopped");
184 }
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190 AssignmentManager am = services.getAssignmentManager();
191 List<HRegionInfo> regionsInTransition = am.processServerShutdown(serverName);
192 LOG.info("Reassigning " + ((hris == null)? 0: hris.size()) +
193 " region(s) that " + (serverName == null? "null": serverName) +
194 " was carrying (and " + regionsInTransition.size() +
195 " regions(s) that were opening on this server)");
196
197 List<HRegionInfo> toAssignRegions = new ArrayList<HRegionInfo>();
198 toAssignRegions.addAll(regionsInTransition);
199
200
201 if (hris != null) {
202 RegionStates regionStates = am.getRegionStates();
203 for (Map.Entry<HRegionInfo, Result> e: hris.entrySet()) {
204 HRegionInfo hri = e.getKey();
205 if (regionsInTransition.contains(hri)) {
206 continue;
207 }
208 RegionState rit = regionStates.getRegionTransitionState(hri);
209 if (processDeadRegion(hri, e.getValue(), am, server.getCatalogTracker())) {
210 ServerName addressFromAM = regionStates.getRegionServerOfRegion(hri);
211 if (addressFromAM != null && !addressFromAM.equals(this.serverName)) {
212
213
214 LOG.info("Skip assigning region " + hri.getRegionNameAsString()
215 + " because it has been opened in " + addressFromAM.getServerName());
216 continue;
217 }
218 if (rit != null) {
219 if (!rit.isOnServer(serverName)
220 || rit.isClosed() || rit.isOpened() || rit.isSplit()) {
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223 LOG.info("Skip assigning region " + rit);
224 continue;
225 }
226 try{
227
228 LOG.info("Reassigning region with rs = " + rit + " and deleting zk node if exists");
229 ZKAssign.deleteNodeFailSilent(services.getZooKeeper(), hri);
230 } catch (KeeperException ke) {
231 this.server.abort("Unexpected ZK exception deleting unassigned node " + hri, ke);
232 return;
233 }
234 }
235 toAssignRegions.add(hri);
236 } else if (rit != null) {
237 if (rit.isSplitting() || rit.isSplit()) {
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244 am.regionOffline(hri);
245 } else if ((rit.isClosing() || rit.isPendingClose())
246 && am.getZKTable().isDisablingOrDisabledTable(hri.getTableNameAsString())) {
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252 am.deleteClosingOrClosedNode(hri);
253 am.regionOffline(hri);
254 } else {
255 LOG.warn("THIS SHOULD NOT HAPPEN: unexpected region in transition "
256 + rit + " not to be assigned by SSH of server " + serverName);
257 }
258 }
259 }
260 }
261 try {
262 am.assign(toAssignRegions);
263 } catch (InterruptedException ie) {
264 LOG.error("Caught " + ie + " during round-robin assignment");
265 throw new IOException(ie);
266 }
267 } finally {
268 this.deadServers.finish(serverName);
269 }
270 LOG.info("Finished processing of shutdown of " + serverName);
271 }
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283 public static boolean processDeadRegion(HRegionInfo hri, Result result,
284 AssignmentManager assignmentManager, CatalogTracker catalogTracker)
285 throws IOException {
286 boolean tablePresent = assignmentManager.getZKTable().isTablePresent(
287 hri.getTableNameAsString());
288 if (!tablePresent) {
289 LOG.info("The table " + hri.getTableNameAsString()
290 + " was deleted. Hence not proceeding.");
291 return false;
292 }
293
294 boolean disabled = assignmentManager.getZKTable().isDisabledTable(
295 hri.getTableNameAsString());
296 if (disabled){
297 LOG.info("The table " + hri.getTableNameAsString()
298 + " was disabled. Hence not proceeding.");
299 return false;
300 }
301 if (hri.isOffline() && hri.isSplit()) {
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305 return false;
306 }
307 boolean disabling = assignmentManager.getZKTable().isDisablingTable(
308 hri.getTableNameAsString());
309 if (disabling) {
310 LOG.info("The table " + hri.getTableNameAsString()
311 + " is disabled. Hence not assigning region" + hri.getEncodedName());
312 return false;
313 }
314 return true;
315 }
316 }