Hi all, I tried to upgrade single node ZK server from 3.4.14 to 3.5.6. There were no snapshot files, so as suggested in ZOOKEEPER-3056 <https://issues.apache.org/jira/browse/ZOOKEEPER-3056>, I have set snapshot.trust.empty to true. After server startup, when I tried to list the znodes, I found that znodes are missing.
Looking into the source code, https://github.com/apache/zookeeper/blob/release-3.5.6/zookeeper-server/src/main/java/org/apache/zookeeper/server/persistence/FileTxnSnapLog.java#L224 looks like we are not reading transaction log if there are no snapshot files and snapshot.trust.empty is set to true. Appreciate any thoughts on this? ZK 3.5.6 logs: [2019-12-07 12:13:35,007] INFO Created server with tickTime 3000 minSessionTimeout 6000 maxSessionTimeout 60000 datadir /var/lib/zookeeper/version-2 snapdir /var/lib/zookeeper/version-2 (org.apache.zookeeper.server.ZooKeeperServer) [2019-12-07 12:13:35,012] INFO Using org.apache.zookeeper.server.NIOServerCnxnFactory as server connection factory (org.apache.zookeeper.server.ServerCnxnFactory) [2019-12-07 12:13:35,014] INFO Configuring NIO connection handler with 10s sessionless connection timeout, 1 selector thread(s), 12 worker threads, and 64 kB direct buffers. (org.apache .zookeeper.server.NIOServerCnxnFactory) [2019-12-07 12:13:35,017] INFO binding to port 0.0.0.0/0.0.0.0:2181 (org.apache.zookeeper.server.NIOServerCnxnFactory) [2019-12-07 12:13:35,027] INFO zookeeper.snapshotSizeFactor = 0.33 (org.apache.zookeeper.server.ZKDatabase) [2019-12-07 12:13:35,029] DEBUG Created new input stream /var/lib/zookeeper/version-2/log.1 (org.apache.zookeeper.server.persistence.FileTxnLog) [2019-12-07 12:13:35,031] DEBUG Created new input archive /var/lib/zookeeper/version-2/log.1 (org.apache.zookeeper.server.persistence.FileTxnLog) [2019-12-07 12:13:35,035] DEBUG EOF exception java.io.EOFException: Failed to read /var/lib/zookeeper/version-2/log.1 (org.apache.zookeeper.server.persistence.FileTxnLog) [2019-12-07 12:13:35,035] WARN No snapshot found, but there are log entries. This should only be allowed during upgrading. (org.apache.zookeeper.server.persistence.FileTxnSnapLog) [2019-12-07 12:13:35,035] INFO Snapshotting: 0x0 to /var/lib/zookeeper/version-2/snapshot.0 (org.apache.zookeeper.server.persistence.FileTxnSnapLog) [2019-12-07 12:13:35,036] INFO Snapshotting: 0x0 to /var/lib/zookeeper/version-2/snapshot.0 (org.apache.zookeeper.server.persistence.FileTxnSnapLog) [2019-12-07 12:13:35,050] INFO Using checkIntervalMs=60000 maxPerMinute=10000 (org.apache.zookeeper.server.ContainerManager) [2019-12-07 12:15:07,137] DEBUG Accepted socket connection from / 127.0.0.1:38888 (org.apache.zookeeper.server.NIOServerCnxnFactory) [2019-12-07 12:15:07,144] DEBUG Session establishment request from client / 127.0.0.1:38888 client's lastZxid is 0x0 (org.apache.zookeeper.server.ZooKeeperServer) [2019-12-07 12:15:07,145] DEBUG Adding session 0x100006e15fb0000 (org.apache.zookeeper.server.SessionTrackerImpl) [2019-12-07 12:15:07,148] TRACE SessionTrackerImpl --- Adding session 0x100006e15fb0000 30000 (org.apache.zookeeper.server.SessionTrackerImpl) [2019-12-07 12:15:07,149] DEBUG Client attempting to establish new session: session = 0x100006e15fb0000, zxid = 0x0, timeout = 30000, address = / 127.0.0.1:38888 (org.apache.zookeeper.server.ZooKeeperServer) [2019-12-07 12:15:07,155] TRACE :Psessionid:0x100006e15fb0000 type:createSession cxid:0x0 zxid:0xfffffffffffffffe txntype:unknown reqpath:n/a (org.apache.zookeeper.server.PrepRequestProcessor) [2019-12-07 12:15:07,155] TRACE SessionTrackerImpl --- Existing session 0x100006e15fb0000 30000 (org.apache.zookeeper.server.SessionTrackerImpl) [2019-12-07 12:15:07,155] INFO Creating new log file: log.1 (org.apache.zookeeper.server.persistence.FileTxnLog) [2019-12-07 12:15:07,170] DEBUG Processing request:: sessionid:0x100006e15fb0000 type:createSession cxid:0x0 zxid:0x1 txntype:-10 reqpath:n/a (org.apache.zookeeper.server.FinalRequestProcessor) Thanks, Manikumar
