Here is how you do grep in windows using powershell. PS G:\> Get-ChildItem -Path G:\messages\processed | Select-String -Pattern “string pattern” | Measure-Object -Line
Find your tomcat version
Sometimes you might need to figure out your tomcat version from within the folder where you run tomcat from. The below command will help you get the details. java -cp lib/catalina.jar org.apache.catalina.util.ServerInfo /usr/share/tomcat7$ java -cp lib/catalina.jar org.apache.catalina.util.ServerInfo Server version: Apache Tomcat/7.0.81 Server built: Aug 11 2017 10:21:27 UTC Server number: 7.0.81.0 OS Name: Linux OS… Continue reading Find your tomcat version
how to wget from a site with authentication
when you got to download from a site that ask for authentication details use the below flags to specify the user and password details wget –user=’yourusernamehere’ –password=’yourpasswordhere’ –auth-no-challenge https://yoururlhere.com
ERROR 1217 (23000) at line 287: Cannot delete or update a parent row: a foreign key constraint fails
ERROR 1217 (23000) at line 287: Cannot delete or update a parent row: a foreign key constraint fails If you got this error, it means that you are trying to restore a database sql file which got dependancy on other tables. To override and restore anyway, add this to the top of the .sql dump… Continue reading ERROR 1217 (23000) at line 287: Cannot delete or update a parent row: a foreign key constraint fails
How to monitor database restore progress
Use the mysql admin tool to see the rows inserted mysqladmin -u root -p extended -r -i 10 |grep ‘Innodb_rows_inserted ‘ Also you can use the processlist command inside mysql to view the activity. This will be best if there are no other activities going on the mysql db mysql> show processlist;
ERROR 2006 (HY000) at line 257: MySQL server has gone away
ERROR 2006 (HY000) at line 257: MySQL server has gone away When doing a mysql dump to the database, if you get this error, it means that you have a connection timeout on the database or your restore is doing a chunk of data that exceeds the max allowed packets. Solution: If you are on… Continue reading ERROR 2006 (HY000) at line 257: MySQL server has gone away
Mysql database size
Find the database size of each database Run the below query at the mysql prompt SELECT table_schema “Data Base Name”, sum( data_length + index_length ) / 1024 / 1024 “Data Base Size in MB”, sum( data_free )/ 1024 / 1024 “Free Space in MB” FROM information_schema.TABLES GROUP BY table_schema ;
unidentified developer – Mac installation of software
Any app downloaded from sources other than appstore might have prompted you with the error like below. can’t be opened as it is from an unidentified developer You will not have the button to open the application. Most tricks to click on the application while holding ctrl or alt key will will not work. The… Continue reading unidentified developer – Mac installation of software
How to generate JVM Heap dump
Find the process Id of the java process In linux. Go to command line. ps aux | grep ‘java’ To generate the dump. jmap -dump:format=b,file=/tmp/heapdump-001.hprof <process id> $ jmap -dump:format=b,file=/tmp/heapdump-001.hprof 31467 Dumping heap to /tmp/heapdump-001.hprof … Heap dump file created The dump file wil be generated at /tmp/heapdump-001.hprof. $ ls -al… Continue reading How to generate JVM Heap dump