for Redhat Linux

list all the repositories

Common Linux

find current folder size

1 2	findmnt /tmp -o SOURCE,FSTYPE,SIZE,USED,AVAIL,USE%,TARGET findmnt /var -o AVAIL

check current user group

1 2	$ groups username $ usermod -a -G groupname username

check RAM and CPU information

1	cat /proc/cpuinfo

subscription-manager

subscription-manager repos --disable '*Hortonworks*'
subscription-manager repos --enable Hortonworks_Ambari_2_5_1_0_RHEL7 --enable Hortonworks_Ambari_2_4_2_0_RHEL7 --enable Hortonworks_HDP-UTILS_1_1_0_21_RHEL7
#check existing package included in certain repo
yum list available | grep Hortonworks_Ambari_2_5_1_0_RHEL7

find port 7000 is used by which process

1	# fuser 7000/tcp