find . -name "*.java" -type f
find all the files within a director and its sub-directory ended with .java
rm *~
delete all the files ended with ~
grep setup BotConfigTODO > log
(grep the lines including setup keyword and save it in a file called log)
ps aux | grep ‘less Dockerfile‘| awk ‘{print $2}‘ | head -1 | xargs kill -9
(Kill the first greped process)
docker exec -i cassandra /bin/bash -c "cat -- > InsertStackState.txt" < InsertStackState.txt
docker exec -it cassandra bash
find ./* -iname "pom.xml"
zless dash-container.log.2015-10-13_10.gz
zgrep 19363011 dash-container.log.2015-10-13_10.gz --color
docker stop service_name (restart - if service dint failed already)
u need to be in that node
if it already failed - fleetctl start service_name
head -5 science.txt
tail -5 science.txt
grep -ivc ‘keyword science’ science.txt
-v display those lines that do NOT match
-n precede each matching line with the line number
-c print only the total count of matched lines
netstat -a | grep LISTEN
Check the top 10 memory/cpu eaters
ps aux --sort=-%mem | awk ‘NR<=10{print $0}‘
Check the default heap size of jvm
java -XX:+PrintFlagsFinal -version | grep HeapSize
Check the access and modification time of a file
stat filename.txt
Run commands in the background
1. command & ：command running in the background will be stopped if you close the terminal/session
2. nohup command & ： command will still run in the background even if you close the terminal/session
Get unique string from lines in a file
grep -o ‘sysToteId.*‘ IMS.txt | sort -u | cut -f1 -d‘,‘ | uniq | less -S | wc -l
zgrep "Broadcasting MoveBinsToInventoryManagementNotification.*MIXED_PRODUCT_PURGING" dash-container.log.2016-05-14_*.gz | grep -o ‘sysToteId.*‘ | sort -u | cut -f1 -d‘,‘ | uniq | less -S | wc -l
Or
zgrep "Broadcasting MoveBinsToInventoryManagementNotification.*MIXED_PRODUCT_PURGING" dash-container.log.2016-05-14_*.gz | grep -o ‘sysToteId.*,‘ | grep -o ^[^,]* | uniq | less -S
Check whether disk is full
#!/bin/bash
disk_usage=$(df -h | grep "sda5" | awk ‘{split($5,p,"%"); print p[1]}‘)
if [ "$disk_usage" -gt 90 ]; then
echo -e "Disk is full, usage is \e[1;31m$disk_usage%\e[0m"
echo "Disk is full, usage is $disk_usage%" | mailx -r "[email protected]" -s "SUBJECT" "[email protected]"
Fi
Onsite Version
checkDiskUsage.sh is
#!/bin/bash
export PROFILE=andoverambientCR1
disk_usage=$(df -h | grep "vg-root" | awk ‘{split($5,p,"%"); print p[1]}‘)
if [ "$disk_usage" -gt 85 ]; then
echo -e "$PROFILE Disk is full, usage is \e[1;31m$disk_usage%\e[0m"
echo "$PROFILE Disk is full, usage is $disk_usage%" | mailx -s "$PROFILE Disk is full, usage is $disk_usage%" "[email protected]"
Fi
- Upload the script to the ambient box
- crontab -e
- add
0 * * * * /app/checkDiskUsage.sh > /dev/null 2>&1
Improved Version
#!/bin/bash
export PROFILE=andoverchillCR1
root_disk_usage=$(df -h | grep "vg-root" | awk ‘{split($5,p,"%"); print p[1] }‘)
data_disk_usage=$(df -h | grep "vg-data" | awk ‘{split($5,p,"%"); print p[1] }‘)
email_message="$PROFILE Disk is full, root partition usage is $root_disk_usage% and data partition usage is $data_disk_usage%"
if [ "$data_disk_usage" -gt 85 ] || [ "$root_disk_usage" -gt 85 ]; then
echo "$email_message" | mailx -s "$email_message" [email protected],[email protected]
fi
sed
http://www.grymoire.com/Unix/Sed.html#TOC
s Substitute command
A simple example is changing "day" in the "old" file to "night" in the "new" file:
sed s/day/night/ <old >new
Or another way (for UNIX beginners),
sed s/day/night/ old >new
The character after the s is the delimiter. It is conventionally a slash, because this is what ed, more, and vi use. It can be anything you want
The escaped parentheses (that is, parentheses with backslashes before them) remember a substring of the characters matched by the regular expression. You can use this to exclude part of the characters matched by the regular expression. The "\1" is the first remembered pattern, and the "\2" is the second remembered pattern. Sed has up to nine remembered patterns.
echo abcd123 | sed ‘s/\([a-z]*\).*/\1/‘
This will output "abcd" and delete the numbers.
If you want it to make changes for every word, add a "g" after the last delimiter and use the work-around:
sed ‘s/[^ ][^ ]*/(&)/g‘ <old >new
With no flags, the first matched substitution is changed. With the "g" option, all matches are changed. If you want to modify a particular pattern that is not the first one on the line, you could use "\(" and "\)" to mark each pattern, and use "\1" to put the first pattern back unchanged. This next example keeps the first word on the line but deletes the second:
sed ‘s/\([a-zA-Z]*\) \([a-zA-Z]*\) /\1 /‘ <old >new
Yuck. There is an easier way to do this. You can add a number after the substitution command to indicate you only want to match that particular pattern. Example:
sed ‘s/[a-zA-Z]* //2‘ <old >new
You can combine a number with the g (global) flag. For instance, if you want to leave the first word alone, but change the second, third, etc. to be DELETED instead, use /2g:
sed ‘s/[a-zA-Z]* /DELETED /2g‘ <old >new
There is one more flag that can follow the third delimiter. With it, you can specify a file that will receive the modified data. An example is the following, which will write all lines that start with an even number, followed by a space, to the file even:
sed -n ‘s/^[0-9]*[02468] /&/w even‘ <file
This flag makes the pattern match case insensitive. This will match abc, aBc, ABC, AbC, etc.:
sed -n ‘/abc/I p‘ <old >new
p is the print command
If you need to make two changes, and you didn‘t want to read the manual, you could pipe together multiple sed commands:
sed ‘s/BEGIN/begin/‘ <old | sed ‘s/END/end/‘ >new
This used two processes instead of one. A sed guru never uses two processes when one can do.
One method of combining multiple commands is to use a -e before each command:
sed -e ‘s/a/A/‘ -e ‘s/b/B/‘ <old >new
If you have many commands and they won‘t fit neatly on one line, you can break up the line using a backslash:
sed -e ‘s/a/A/g‘ \
-e ‘s/e/E/g‘ \
-e ‘s/i/I/g‘ \
-e ‘s/o/O/g‘ \
-e ‘s/u/U/g‘ <old >new