XWiki error at starting time, maybe related to the descriptor or database query

I am debugging an old instance of XWiki, trying to bring it up, get familiar with it, and then upgrade to the up-to-date versions. Unfortunately, the instance is a testing server broken down for a long time, so I guess the version is XWiki Enterprise 7.0.1 from the running production.

After starting Tomcat, I see the tables get created in the MariaDB database. However, the browser gets the below exception. Please see the full error stack attached at the end of the post.

...
java.lang.RuntimeException: Failed to located wiki descriptor for alias [hostname]
...
org.xwiki.query.QueryException: Exception while executing query. Query statement = [ select doc.fullName from XWikiDocument as doc , BaseObject as _o1 where ( doc.object ( XWiki.XWikiServerClass ) . server = :wikiAlias and doc.name like 'XWikiServer%' ) and doc.fullName=_o1.name and _o1.className='XWiki.XWikiServerClass' ]
...

I am new to this area and unsure what descriptor means in the above message, so I would highly appreciate any hints or suggestions on the issue’s background and how to fix it.

Technical Details:

The full error stack on the browser:

HTTP Status 500 - com.xpn.xwiki.XWikiException: Error number 11007 in 0: Failed to extract Entity Resource Reference from URL [http://hostname/bin/view/Main/]

type Exception report

message com.xpn.xwiki.XWikiException: Error number 11007 in 0: Failed to extract Entity Resource Reference from URL [http://hostname/bin/view/Main/]

description The server encountered an internal error that prevented it from fulfilling this request.

exception

javax.servlet.ServletException: com.xpn.xwiki.XWikiException: Error number 11007 in 0: Failed to extract Entity Resource Reference from URL [http://hostname/bin/view/Main/]
	org.apache.struts.action.RequestProcessor.processException(RequestProcessor.java:520)
	org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:427)
	org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:228)
	org.apache.struts.action.ActionServlet.process(ActionServlet.java:1913)
	org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:449)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:622)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
	com.xpn.xwiki.web.ActionFilter.doFilter(ActionFilter.java:115)
	org.xwiki.wysiwyg.server.filter.ConversionFilter.doFilter(ConversionFilter.java:127)
	org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
	org.xwiki.container.servlet.filters.internal.SetHTTPHeaderFilter.doFilter(SetHTTPHeaderFilter.java:63)
	com.xpn.xwiki.plugin.webdav.XWikiDavFilter.doFilter(XWikiDavFilter.java:66)
	org.xwiki.container.servlet.filters.internal.SavedRequestRestorerFilter.doFilter(SavedRequestRestorerFilter.java:208)
	org.xwiki.container.servlet.filters.internal.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:111)

root cause

com.xpn.xwiki.XWikiException: Error number 11007 in 0: Failed to extract Entity Resource Reference from URL [http://hostname/bin/view/Main/]
	com.xpn.xwiki.XWiki.initializeResourceFromURL(XWiki.java:645)
	com.xpn.xwiki.XWiki.getXWiki(XWiki.java:593)
	com.xpn.xwiki.web.XWikiAction.execute(XWikiAction.java:170)
	com.xpn.xwiki.web.XWikiAction.execute(XWikiAction.java:146)
	org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:425)
	org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:228)
	org.apache.struts.action.ActionServlet.process(ActionServlet.java:1913)
	org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:449)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:622)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
	com.xpn.xwiki.web.ActionFilter.doFilter(ActionFilter.java:115)
	org.xwiki.wysiwyg.server.filter.ConversionFilter.doFilter(ConversionFilter.java:127)
	org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
	org.xwiki.container.servlet.filters.internal.SetHTTPHeaderFilter.doFilter(SetHTTPHeaderFilter.java:63)
	com.xpn.xwiki.plugin.webdav.XWikiDavFilter.doFilter(XWikiDavFilter.java:66)
	org.xwiki.container.servlet.filters.internal.SavedRequestRestorerFilter.doFilter(SavedRequestRestorerFilter.java:208)
	org.xwiki.container.servlet.filters.internal.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:111)

root cause

java.lang.RuntimeException: Failed to located wiki descriptor for alias [hostname]
	org.xwiki.url.internal.standard.AbstractWikiReferenceExtractor.getWikiDescriptorByAlias(AbstractWikiReferenceExtractor.java:78)
	org.xwiki.url.internal.standard.DomainWikiReferenceExtractor.resolveDomainBasedWikiReference(DomainWikiReferenceExtractor.java:61)
	org.xwiki.url.internal.standard.DomainWikiReferenceExtractor.extract(DomainWikiReferenceExtractor.java:47)
	org.xwiki.url.internal.standard.entity.BinEntityResourceReferenceResolver.extractWikiReference(BinEntityResourceReferenceResolver.java:51)
	org.xwiki.url.internal.standard.entity.AbstractEntityResourceReferenceResolver.resolve(AbstractEntityResourceReferenceResolver.java:61)
	org.xwiki.url.internal.standard.entity.AbstractEntityResourceReferenceResolver.resolve(AbstractEntityResourceReferenceResolver.java:45)
	org.xwiki.url.internal.standard.StandardURLResourceReferenceResolver.resolve(StandardURLResourceReferenceResolver.java:201)
	org.xwiki.url.internal.standard.StandardURLResourceReferenceResolver.resolve(StandardURLResourceReferenceResolver.java:55)
	org.xwiki.url.internal.DefaultResourceReferenceResolver.resolve(DefaultResourceReferenceResolver.java:75)
	org.xwiki.url.internal.DefaultResourceReferenceResolver.resolve(DefaultResourceReferenceResolver.java:45)
	com.xpn.xwiki.XWiki.initializeResourceFromURL(XWiki.java:641)
	com.xpn.xwiki.XWiki.getXWiki(XWiki.java:593)
	com.xpn.xwiki.web.XWikiAction.execute(XWikiAction.java:170)
	com.xpn.xwiki.web.XWikiAction.execute(XWikiAction.java:146)
	org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:425)
	org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:228)
	org.apache.struts.action.ActionServlet.process(ActionServlet.java:1913)
	org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:449)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:622)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
	com.xpn.xwiki.web.ActionFilter.doFilter(ActionFilter.java:115)
	org.xwiki.wysiwyg.server.filter.ConversionFilter.doFilter(ConversionFilter.java:127)
	org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
	org.xwiki.container.servlet.filters.internal.SetHTTPHeaderFilter.doFilter(SetHTTPHeaderFilter.java:63)
	com.xpn.xwiki.plugin.webdav.XWikiDavFilter.doFilter(XWikiDavFilter.java:66)
	org.xwiki.container.servlet.filters.internal.SavedRequestRestorerFilter.doFilter(SavedRequestRestorerFilter.java:208)
	org.xwiki.container.servlet.filters.internal.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:111)

root cause

org.xwiki.wiki.manager.WikiManagerException: Failed to locate XWiki.XWikiServerClass document for wiki alias [hostname]
	org.xwiki.wiki.internal.descriptor.document.DefaultWikiDescriptorDocumentHelper.findXWikiServerClassDocumentReference(DefaultWikiDescriptorDocumentHelper.java:119)
	org.xwiki.wiki.internal.descriptor.document.DefaultWikiDescriptorDocumentHelper.findXWikiServerClassDocument(DefaultWikiDescriptorDocumentHelper.java:131)
	org.xwiki.wiki.internal.descriptor.DefaultWikiDescriptorManager.getByAlias(DefaultWikiDescriptorManager.java:144)
	org.xwiki.url.internal.standard.AbstractWikiReferenceExtractor.getWikiDescriptorByAlias(AbstractWikiReferenceExtractor.java:76)
	org.xwiki.url.internal.standard.DomainWikiReferenceExtractor.resolveDomainBasedWikiReference(DomainWikiReferenceExtractor.java:61)
	org.xwiki.url.internal.standard.DomainWikiReferenceExtractor.extract(DomainWikiReferenceExtractor.java:47)
	org.xwiki.url.internal.standard.entity.BinEntityResourceReferenceResolver.extractWikiReference(BinEntityResourceReferenceResolver.java:51)
	org.xwiki.url.internal.standard.entity.AbstractEntityResourceReferenceResolver.resolve(AbstractEntityResourceReferenceResolver.java:61)
	org.xwiki.url.internal.standard.entity.AbstractEntityResourceReferenceResolver.resolve(AbstractEntityResourceReferenceResolver.java:45)
	org.xwiki.url.internal.standard.StandardURLResourceReferenceResolver.resolve(StandardURLResourceReferenceResolver.java:201)
	org.xwiki.url.internal.standard.StandardURLResourceReferenceResolver.resolve(StandardURLResourceReferenceResolver.java:55)
	org.xwiki.url.internal.DefaultResourceReferenceResolver.resolve(DefaultResourceReferenceResolver.java:75)
	org.xwiki.url.internal.DefaultResourceReferenceResolver.resolve(DefaultResourceReferenceResolver.java:45)
	com.xpn.xwiki.XWiki.initializeResourceFromURL(XWiki.java:641)
	com.xpn.xwiki.XWiki.getXWiki(XWiki.java:593)
	com.xpn.xwiki.web.XWikiAction.execute(XWikiAction.java:170)
	com.xpn.xwiki.web.XWikiAction.execute(XWikiAction.java:146)
	org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:425)
	org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:228)
	org.apache.struts.action.ActionServlet.process(ActionServlet.java:1913)
	org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:449)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:622)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
	com.xpn.xwiki.web.ActionFilter.doFilter(ActionFilter.java:115)
	org.xwiki.wysiwyg.server.filter.ConversionFilter.doFilter(ConversionFilter.java:127)
	org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
	org.xwiki.container.servlet.filters.internal.SetHTTPHeaderFilter.doFilter(SetHTTPHeaderFilter.java:63)
	com.xpn.xwiki.plugin.webdav.XWikiDavFilter.doFilter(XWikiDavFilter.java:66)
	org.xwiki.container.servlet.filters.internal.SavedRequestRestorerFilter.doFilter(SavedRequestRestorerFilter.java:208)
	org.xwiki.container.servlet.filters.internal.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:111)

root cause

org.xwiki.query.QueryException: Exception while executing query. Query statement = [ select doc.fullName from XWikiDocument as doc , BaseObject as _o1 where ( doc.object ( XWiki.XWikiServerClass ) . server = :wikiAlias and doc.name like 'XWikiServer%' ) and doc.fullName=_o1.name and _o1.className='XWiki.XWikiServerClass' ]
	com.xpn.xwiki.store.hibernate.query.HqlQueryExecutor.execute(HqlQueryExecutor.java:109)
	org.xwiki.query.internal.DefaultQueryExecutorManager.execute(DefaultQueryExecutorManager.java:71)
	org.xwiki.query.internal.DefaultQuery.execute(DefaultQuery.java:248)
	org.xwiki.query.xwql.internal.XWQLQueryExecutor.execute(XWQLQueryExecutor.java:97)
	org.xwiki.query.internal.DefaultQueryExecutorManager.execute(DefaultQueryExecutorManager.java:71)
	org.xwiki.query.internal.DefaultQuery.execute(DefaultQuery.java:248)
	org.xwiki.wiki.internal.descriptor.document.DefaultWikiDescriptorDocumentHelper.findXWikiServerClassDocumentReference(DefaultWikiDescriptorDocumentHelper.java:112)
	org.xwiki.wiki.internal.descriptor.document.DefaultWikiDescriptorDocumentHelper.findXWikiServerClassDocument(DefaultWikiDescriptorDocumentHelper.java:131)
	org.xwiki.wiki.internal.descriptor.DefaultWikiDescriptorManager.getByAlias(DefaultWikiDescriptorManager.java:144)
	org.xwiki.url.internal.standard.AbstractWikiReferenceExtractor.getWikiDescriptorByAlias(AbstractWikiReferenceExtractor.java:76)
	org.xwiki.url.internal.standard.DomainWikiReferenceExtractor.resolveDomainBasedWikiReference(DomainWikiReferenceExtractor.java:61)
	org.xwiki.url.internal.standard.DomainWikiReferenceExtractor.extract(DomainWikiReferenceExtractor.java:47)
	org.xwiki.url.internal.standard.entity.BinEntityResourceReferenceResolver.extractWikiReference(BinEntityResourceReferenceResolver.java:51)
	org.xwiki.url.internal.standard.entity.AbstractEntityResourceReferenceResolver.resolve(AbstractEntityResourceReferenceResolver.java:61)
	org.xwiki.url.internal.standard.entity.AbstractEntityResourceReferenceResolver.resolve(AbstractEntityResourceReferenceResolver.java:45)
	org.xwiki.url.internal.standard.StandardURLResourceReferenceResolver.resolve(StandardURLResourceReferenceResolver.java:201)
	org.xwiki.url.internal.standard.StandardURLResourceReferenceResolver.resolve(StandardURLResourceReferenceResolver.java:55)
	org.xwiki.url.internal.DefaultResourceReferenceResolver.resolve(DefaultResourceReferenceResolver.java:75)
	org.xwiki.url.internal.DefaultResourceReferenceResolver.resolve(DefaultResourceReferenceResolver.java:45)
	com.xpn.xwiki.XWiki.initializeResourceFromURL(XWiki.java:641)
	com.xpn.xwiki.XWiki.getXWiki(XWiki.java:593)
	com.xpn.xwiki.web.XWikiAction.execute(XWikiAction.java:170)
	com.xpn.xwiki.web.XWikiAction.execute(XWikiAction.java:146)
	org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:425)
	org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:228)
	org.apache.struts.action.ActionServlet.process(ActionServlet.java:1913)
	org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:449)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:622)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
	com.xpn.xwiki.web.ActionFilter.doFilter(ActionFilter.java:115)
	org.xwiki.wysiwyg.server.filter.ConversionFilter.doFilter(ConversionFilter.java:127)
	org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
	org.xwiki.container.servlet.filters.internal.SetHTTPHeaderFilter.doFilter(SetHTTPHeaderFilter.java:63)
	com.xpn.xwiki.plugin.webdav.XWikiDavFilter.doFilter(XWikiDavFilter.java:66)
	org.xwiki.container.servlet.filters.internal.SavedRequestRestorerFilter.doFilter(SavedRequestRestorerFilter.java:208)
	org.xwiki.container.servlet.filters.internal.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:111)

root cause

com.xpn.xwiki.XWikiException: Error number 0 in 3: Exception while hibernate execute
	com.xpn.xwiki.store.XWikiHibernateBaseStore.execute(XWikiHibernateBaseStore.java:1305)
	com.xpn.xwiki.store.XWikiHibernateBaseStore.executeRead(XWikiHibernateBaseStore.java:1366)
	com.xpn.xwiki.store.hibernate.query.HqlQueryExecutor.execute(HqlQueryExecutor.java:90)
	org.xwiki.query.internal.DefaultQueryExecutorManager.execute(DefaultQueryExecutorManager.java:71)
	org.xwiki.query.internal.DefaultQuery.execute(DefaultQuery.java:248)
	org.xwiki.query.xwql.internal.XWQLQueryExecutor.execute(XWQLQueryExecutor.java:97)
	org.xwiki.query.internal.DefaultQueryExecutorManager.execute(DefaultQueryExecutorManager.java:71)
	org.xwiki.query.internal.DefaultQuery.execute(DefaultQuery.java:248)
	org.xwiki.wiki.internal.descriptor.document.DefaultWikiDescriptorDocumentHelper.findXWikiServerClassDocumentReference(DefaultWikiDescriptorDocumentHelper.java:112)
	org.xwiki.wiki.internal.descriptor.document.DefaultWikiDescriptorDocumentHelper.findXWikiServerClassDocument(DefaultWikiDescriptorDocumentHelper.java:131)
	org.xwiki.wiki.internal.descriptor.DefaultWikiDescriptorManager.getByAlias(DefaultWikiDescriptorManager.java:144)
	org.xwiki.url.internal.standard.AbstractWikiReferenceExtractor.getWikiDescriptorByAlias(AbstractWikiReferenceExtractor.java:76)
	org.xwiki.url.internal.standard.DomainWikiReferenceExtractor.resolveDomainBasedWikiReference(DomainWikiReferenceExtractor.java:61)
	org.xwiki.url.internal.standard.DomainWikiReferenceExtractor.extract(DomainWikiReferenceExtractor.java:47)
	org.xwiki.url.internal.standard.entity.BinEntityResourceReferenceResolver.extractWikiReference(BinEntityResourceReferenceResolver.java:51)
	org.xwiki.url.internal.standard.entity.AbstractEntityResourceReferenceResolver.resolve(AbstractEntityResourceReferenceResolver.java:61)
	org.xwiki.url.internal.standard.entity.AbstractEntityResourceReferenceResolver.resolve(AbstractEntityResourceReferenceResolver.java:45)
	org.xwiki.url.internal.standard.StandardURLResourceReferenceResolver.resolve(StandardURLResourceReferenceResolver.java:201)
	org.xwiki.url.internal.standard.StandardURLResourceReferenceResolver.resolve(StandardURLResourceReferenceResolver.java:55)
	org.xwiki.url.internal.DefaultResourceReferenceResolver.resolve(DefaultResourceReferenceResolver.java:75)
	org.xwiki.url.internal.DefaultResourceReferenceResolver.resolve(DefaultResourceReferenceResolver.java:45)
	com.xpn.xwiki.XWiki.initializeResourceFromURL(XWiki.java:641)
	com.xpn.xwiki.XWiki.getXWiki(XWiki.java:593)
	com.xpn.xwiki.web.XWikiAction.execute(XWikiAction.java:170)
	com.xpn.xwiki.web.XWikiAction.execute(XWikiAction.java:146)
	org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:425)
	org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:228)
	org.apache.struts.action.ActionServlet.process(ActionServlet.java:1913)
	org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:449)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:622)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
	com.xpn.xwiki.web.ActionFilter.doFilter(ActionFilter.java:115)
	org.xwiki.wysiwyg.server.filter.ConversionFilter.doFilter(ConversionFilter.java:127)
	org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
	org.xwiki.container.servlet.filters.internal.SetHTTPHeaderFilter.doFilter(SetHTTPHeaderFilter.java:63)
	com.xpn.xwiki.plugin.webdav.XWikiDavFilter.doFilter(XWikiDavFilter.java:66)
	org.xwiki.container.servlet.filters.internal.SavedRequestRestorerFilter.doFilter(SavedRequestRestorerFilter.java:208)
	org.xwiki.container.servlet.filters.internal.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:111)

root cause

java.lang.NullPointerException
	org.hibernate.hql.ast.HqlSqlWalker.lookupProperty(HqlSqlWalker.java:560)
	org.hibernate.hql.antlr.HqlSqlBaseWalker.addrExpr(HqlSqlBaseWalker.java:4774)
	org.hibernate.hql.antlr.HqlSqlBaseWalker.expr(HqlSqlBaseWalker.java:1326)
	org.hibernate.hql.antlr.HqlSqlBaseWalker.exprOrSubquery(HqlSqlBaseWalker.java:4471)
	org.hibernate.hql.antlr.HqlSqlBaseWalker.comparisonExpr(HqlSqlBaseWalker.java:3944)
	org.hibernate.hql.antlr.HqlSqlBaseWalker.logicalExpr(HqlSqlBaseWalker.java:2047)
	org.hibernate.hql.antlr.HqlSqlBaseWalker.logicalExpr(HqlSqlBaseWalker.java:1972)
	org.hibernate.hql.antlr.HqlSqlBaseWalker.logicalExpr(HqlSqlBaseWalker.java:1972)
	org.hibernate.hql.antlr.HqlSqlBaseWalker.logicalExpr(HqlSqlBaseWalker.java:1972)
	org.hibernate.hql.antlr.HqlSqlBaseWalker.whereClause(HqlSqlBaseWalker.java:831)
	org.hibernate.hql.antlr.HqlSqlBaseWalker.query(HqlSqlBaseWalker.java:617)
	org.hibernate.hql.antlr.HqlSqlBaseWalker.selectStatement(HqlSqlBaseWalker.java:301)
	org.hibernate.hql.antlr.HqlSqlBaseWalker.statement(HqlSqlBaseWalker.java:244)
	org.hibernate.hql.ast.QueryTranslatorImpl.analyze(QueryTranslatorImpl.java:256)
	org.hibernate.hql.ast.QueryTranslatorImpl.doCompile(QueryTranslatorImpl.java:187)
	org.hibernate.hql.ast.QueryTranslatorImpl.compile(QueryTranslatorImpl.java:138)
	org.hibernate.engine.query.HQLQueryPlan.<init>(HQLQueryPlan.java:101)
	org.hibernate.engine.query.HQLQueryPlan.<init>(HQLQueryPlan.java:80)
	org.hibernate.engine.query.QueryPlanCache.getHQLQueryPlan(QueryPlanCache.java:124)
	org.hibernate.impl.AbstractSessionImpl.getHQLQueryPlan(AbstractSessionImpl.java:156)
	org.hibernate.impl.AbstractSessionImpl.createQuery(AbstractSessionImpl.java:135)
	org.hibernate.impl.SessionImpl.createQuery(SessionImpl.java:1770)
	com.xpn.xwiki.store.hibernate.query.HqlQueryExecutor.createHibernateQuery(HqlQueryExecutor.java:157)
	com.xpn.xwiki.store.hibernate.query.HqlQueryExecutor$1.doInHibernate(HqlQueryExecutor.java:96)
	com.xpn.xwiki.store.hibernate.query.HqlQueryExecutor$1.doInHibernate(HqlQueryExecutor.java:91)
	com.xpn.xwiki.store.XWikiHibernateBaseStore.execute(XWikiHibernateBaseStore.java:1299)
	com.xpn.xwiki.store.XWikiHibernateBaseStore.executeRead(XWikiHibernateBaseStore.java:1366)
	com.xpn.xwiki.store.hibernate.query.HqlQueryExecutor.execute(HqlQueryExecutor.java:90)
	org.xwiki.query.internal.DefaultQueryExecutorManager.execute(DefaultQueryExecutorManager.java:71)
	org.xwiki.query.internal.DefaultQuery.execute(DefaultQuery.java:248)
	org.xwiki.query.xwql.internal.XWQLQueryExecutor.execute(XWQLQueryExecutor.java:97)
	org.xwiki.query.internal.DefaultQueryExecutorManager.execute(DefaultQueryExecutorManager.java:71)
	org.xwiki.query.internal.DefaultQuery.execute(DefaultQuery.java:248)
	org.xwiki.wiki.internal.descriptor.document.DefaultWikiDescriptorDocumentHelper.findXWikiServerClassDocumentReference(DefaultWikiDescriptorDocumentHelper.java:112)
	org.xwiki.wiki.internal.descriptor.document.DefaultWikiDescriptorDocumentHelper.findXWikiServerClassDocument(DefaultWikiDescriptorDocumentHelper.java:131)
	org.xwiki.wiki.internal.descriptor.DefaultWikiDescriptorManager.getByAlias(DefaultWikiDescriptorManager.java:144)
	org.xwiki.url.internal.standard.AbstractWikiReferenceExtractor.getWikiDescriptorByAlias(AbstractWikiReferenceExtractor.java:76)
	org.xwiki.url.internal.standard.DomainWikiReferenceExtractor.resolveDomainBasedWikiReference(DomainWikiReferenceExtractor.java:61)
	org.xwiki.url.internal.standard.DomainWikiReferenceExtractor.extract(DomainWikiReferenceExtractor.java:47)
	org.xwiki.url.internal.standard.entity.BinEntityResourceReferenceResolver.extractWikiReference(BinEntityResourceReferenceResolver.java:51)
	org.xwiki.url.internal.standard.entity.AbstractEntityResourceReferenceResolver.resolve(AbstractEntityResourceReferenceResolver.java:61)
	org.xwiki.url.internal.standard.entity.AbstractEntityResourceReferenceResolver.resolve(AbstractEntityResourceReferenceResolver.java:45)
	org.xwiki.url.internal.standard.StandardURLResourceReferenceResolver.resolve(StandardURLResourceReferenceResolver.java:201)
	org.xwiki.url.internal.standard.StandardURLResourceReferenceResolver.resolve(StandardURLResourceReferenceResolver.java:55)
	org.xwiki.url.internal.DefaultResourceReferenceResolver.resolve(DefaultResourceReferenceResolver.java:75)
	org.xwiki.url.internal.DefaultResourceReferenceResolver.resolve(DefaultResourceReferenceResolver.java:45)
	com.xpn.xwiki.XWiki.initializeResourceFromURL(XWiki.java:641)
	com.xpn.xwiki.XWiki.getXWiki(XWiki.java:593)
	com.xpn.xwiki.web.XWikiAction.execute(XWikiAction.java:170)
	com.xpn.xwiki.web.XWikiAction.execute(XWikiAction.java:146)
	org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:425)
	org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:228)
	org.apache.struts.action.ActionServlet.process(ActionServlet.java:1913)
	org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:449)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:622)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
	com.xpn.xwiki.web.ActionFilter.doFilter(ActionFilter.java:115)
	org.xwiki.wysiwyg.server.filter.ConversionFilter.doFilter(ConversionFilter.java:127)
	org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
	org.xwiki.container.servlet.filters.internal.SetHTTPHeaderFilter.doFilter(SetHTTPHeaderFilter.java:63)
	com.xpn.xwiki.plugin.webdav.XWikiDavFilter.doFilter(XWikiDavFilter.java:66)
	org.xwiki.container.servlet.filters.internal.SavedRequestRestorerFilter.doFilter(SavedRequestRestorerFilter.java:208)
	org.xwiki.container.servlet.filters.internal.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:111)

note The full stack trace of the root cause is available in the Apache Tomcat/8.0.22 logs.
Apache Tomcat/8.0.22

Hi,

Can you please provide the full stack trace of this error from the log?

1 Like

In the $CATALINA_HOME directory, I checked file logs/catalina.out.

Firstly, I found multiple exceptions triggered by SSL missing certificate files, with the below error messages. So, I disabled SSL by commenting out the lines like websocket.ssl.xxx in the configuration file webapps/ROOT/WEB-INF/xwiki.properties, then XWiki started correctly.

Partial SSL error:

...
Caused by: java.lang.RuntimeException: java.lang.RuntimeException: SSL enabled with websocket.ssl.certChainFile set but the certChainFile does not seem to exist.
...
Caused by: java.lang.RuntimeException: SSL enabled with websocket.ssl.certChainFile set but the certChainFile does not seem to exist.
...

Moreover, it seems that the Java process needs some time to turn off and release resources like address binding. So, calling systemctl restart tomcat results in the below error because it does not leave enough buffer between the stop and start actions. Therefore, I need to manually call systemctl stop tomcat and then systemctl start tomcat.

...
23-Aug-2022 16:27:53.631 SEVERE [main] org.apache.coyote.AbstractProtocol.init Failed to initialize end point associated with ProtocolHandler ["ajp-nio-8009"]
 java.net.BindException: Address already in use
...

Many thanks to @nikpetrenko for the pointers. Please let me know if I missed a more standard solution or something.

Hi again, glad to hear it. But also, you can change the port number 8009 in server.xml. That should help instead of manually restarting.