Useful Commands & Tools

# Local Linux install

# Export measurement to line protocol

$ sudo influxd inspect export-lp --bucket-id <id> --engine-path /var/lib/influxdb/engine/ --measurement <name> --output-path <path-to-file>

# import measurement from line protocol

$ sudo influx write --org <org> -b <bucket> -f <path-to-file> --token $INFLUX_TOKEN

# delete measurements

$ sudo influx delete --org <org> --bucket <bucket> --start '1970-01-01T00:00:00Z' --stop $(date +"%Y-%m-%dT%H:%M:%SZ") --predicate '_measurement="<name>"' --token $INFLUX_TOKEN

# run v1 client

$ influx v1 shell

# backup

$ influx backup <target dir> -t $INFLUX_TOKEN

# list retention policies

$ influx v1 dbrp list

# create default retention policy

$ influx v1 dbrp create --db <db> --rp autogen --bucket-id <bucketid> --token $INFLUX_TOKEN

Powershell version
PS > $PSVersionTable

Show current user certificate thumbprints
PS > get-ChildItem Cert:\CurrentUser\My

Set Tls version
PS > [Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12

Measure page download time
PS > Measure-Command {Invoke-WebRequest -Uri "https://<>" -CertificateThumbprint ""}

$ curl -s -o /dev/null --cert <pem> --key <pem> --insecure -k "url" -w "URL=%{url_effective} RTT=%{time_total} SIZE=%{size_download} TTFB=%{time_starttransfer} CODE=%{http_code} DNS=%{time_namelookup} CONNECT=%{time_connect} appconnect=%{time_appconnect}\n"

# clone a repository

git clone <repository>

# checkout and track remote branch

git branch -a

# git checkout -b <feature-name> origin/<feature-name>

git status

git add .

git commit -m "commit message"

git push

# If feature branch is behind remote main, update local main and use rebase to preserve history.

git checkout main

git pull

git checkout <feature-name>

git rebase main

# If there are merge conflicts on added/removed files correct this using

git add/rm <filename>

# If there are merge conflicts on changed files, edit the file and remove the unwanted changes and conflict markers. Then add the updated file

git add <filename>

git rebase --continue

# Edit local git config on linux

git config --global --edit

keys *

type <key>

lrange <key> <start> <end>

del key

dbsize

info

type <key>

delete all keys from a redis instance: 

redis-cli keys "*" | xargs -I {} redis-cli del {}

# Print command line flags available for the JVM (https://docs.oracle.com/javase/8/docs/technotes/tools/unix/java.html)

java -XX:+PrintFlagsFinal

# Print ergonomically selected flags for the JVM that appeared on the command line

java -XX:+PrintCommandLineFlags

# Java17 - show the cgroup version, cpu and memory limits.

java -XshowSettings:system

# Print options

jcmd <pid>

# Get flags that can be set using jcmd

jcmd <pid> VM.flags -all | grep manageable

# Set flag

jcmd <pid> VM.set_flag <flag> <value>

# create heap dump of all objects in binary format

jmap -dump:format=b,file=/tmp/dump.hprof <pid>

# Example commands to start JFR using jcmd are shown below.

jcmd <pid> JFR.start duration=60s

jcmd JFR.check

# Unless a filename is specified the default directory data is written to is /tmp.
# By default jfr will chunk up a recording in to separate files. To re-combine these into a single # file for analysis run:

jfr assemble <directory> output-file-name.jfr

# create a jks from pfx
# e.g. from chrome export certificate with all certificates in the chain and include private key

keytool.exe -importkeystore -srckeystore "<name.pfx" -srcstoretype pkcs12 -destkeystore "<name>.jks"

# display cpu by thread for a process

top -H -p <pid>

# sample processes every second, for 30 seconds and output to a file 

top -d 1 -n 30 -b > top-output-processes.txt

# sample threads for a processes every 100ms, for 30 seconds and output to a file 

top -H -p <pid> -d 0.1 -n 300 -b > top-output-threads-100ms.txt

# get the average running thread count for a process in a thread sample (e.g. above)

grep Threads top-output-threads-100ms.txt | tail -299 | tr -s ' ' | cut -d' ' -f4 | awk '{total += $1; n++}END{print total, total/n}'

$ for i in ctr --namespace k8s.io.containers ls | grep <name> | cut -d' ' -f1;
do
ctr --namespace k8s.io task ist | grep $i;
done

e.g. a087b8b5e433f80114dc5104f818d1a183af48bdb23774f0e28f9ee4b43ab5ae 4976 RUNNING

/proc/loadavg

0.29 0.17 0.15 1/586 249213

show dbs

use <db>

db.getCollectionNames()

db.<collection>.getIndexes()

rabbitmq-diagnostics status

rabbitmqctl list_queues

kubectl get pods -n <ns>
kubectl top node
kubectl edit hpa -n <ns>
kubectl edit deployment/<service> -n <ns>
kubectl edit deployment --replicas=n <service> -n <ns>