Bash Useful Commands

bash_cmds.md

Linux Stuff

for i in ls ; do stat $i ; done

iotop - Read Write speeds iftop - Network current speeds

Disks

Test write speed

• dd if=/dev/zero of=/tmp/output bs=8k count=10k; rm -f /tmp/output
• sudo hdparm -v /dev/sda1

Docker stuff

• Check real cgroup limitations for a docker container /sys/fs/cgroup/memory/docker/<DOCKER_ID>

AWK stuf

• Tail 500 errors

tail -f  /var/log/nginx/*.log | awk ' $9 > 500 {print $0}'

CURL

• Useful curl times. Source: https://stackoverflow.com/questions/18215389/how-do-i-measure-request-and-response-times-at-once-using-curl

Create a new file, curl-format.txt, and paste in:

    time_namelookup:  %{time_namelookup}\n
       time_connect:  %{time_connect}\n
    time_appconnect:  %{time_appconnect}\n
   time_pretransfer:  %{time_pretransfer}\n
      time_redirect:  %{time_redirect}\n
 time_starttransfer:  %{time_starttransfer}\n
                    ----------\n
         time_total:  %{time_total}\n

Make a request:

curl -w "@curl-format.txt" -o /dev/null -s "http://wordpress.com/"

FIND

find . -name "pattern" -exec command {} \;

Xargs

nomad node status | grep rt-green | awk '{ print $1 }' | xargs -I{} nomad status {}

Wget

wget -qqO - https://storage.googleapis.com/kubernetes-helm/helm-v2.10.0-linux-amd64.tar.gz | tar xvz --strip-components=1  -C directory/ linux-amd64/helm

Tar

wget -qqO - https://storage.googleapis.com/kubernetes-helm/helm-v2.10.0-linux-amd64.tar.gz | tar xvz --strip-components=1  -C directory/ linux-amd64/helm