TestDisk includes PhotoRec which is very good at recovering files: sudo apt-get install testdisk To run PhotoRec: sudo photorec PhotoRec: http://www.cgsecurity.org/wiki/PhotoRec
Continue readingCopy data from one Hadoop cluster to another Hadoop cluster (running different versions of Hadoop)
I had to copy data from one Hadoop cluster to another recently. However, the two clusters ran different versions of Hadoop, which made using distcp […]
Continue readingUseful Scripts
PowerShell: $ou = [adsi]”LDAP://OU=Marketing,OU=Departments,DC=Company,DC=Domain”; $user = $ou.psbase.get_children().find(‘CN=UserName’); $user.psbase.invokeSet(“allowLogon”,0); $user.setinfo(); Bash: #!/bin/bash fname=”/path/file” tname=”/new/file.tmp” i=”0″ DATE=$(date +%Y%m%d%H%M%S) sudo cp “$fname” “$fname”.$DATE while IFS=” read -r line […]
Continue readingSqoop Server Startup Failure: Upgrade required but not allowed
After an upgrade from CDH 5.0.2 to CDH 5.0.3, Sqoop failed to start with the following error: Server startup failure, Connector registration failed, Upgrade required […]
Continue readingHBase All Regions in Transition: state=FAILED_OPEN
After I added a jar file to the HBase Master I had a problem where regions failed to transition to a RegionServer. Below are the errors; […]
Continue readingCron file failed to load: (username~) ORPHAN (no passwd entry)
This problem bothers me a little. The authentication server failed during a cron job that referenced a specific account. Ubuntu could not authenticate the account, […]
Continue readingCloudera Manager HBase Check HFile Version
An under-documented feature in Cloudera Manager is the HBase Check HFile Version. When upgrading from CDH 4.7 to CDH 5.0, I ran across the instructions that […]
Continue readingCannot Start HBase Master: SplitLogManager: Error Splitting
I could not start HBase within Cloudera Manager, the service reported errors. I was initially confused because I could start the Master when the RegionServers […]
Continue readingSQL Query for Recently Changed Objects
These may be useful to determine when objects have been changed. We might infer from this info when was the last formal deployment of a […]
Continue readingFix an SQL Database Marked Suspect
If you have a database marked suspect, and do not have a backup to restore from, you can attempt to repair the database. This may […]
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