Which port must be open on a firewall, to allow a DNS server to receive queries? (Enter only the port number).

What information is found in the following excerpt from the file /proc/mdstat? (Choose two.)

Which command can be used to scan a specified network looking for IP addresses that appear to be in use?

In the following output, what percentage of time was the CPU waiting for pending I/O?
# vmstat 1 100
procs -----------memory---------- ---swap-- -----io---- --system-- ----cpu---- r b swpd free buff cache si so bi bo in cs us sy id wa
0 0 0 282120 134108 5797012 0 0 0 2 0 0 0 0 100 0
0 0 0 282120 134108 5797012 0 0 0 0 1007 359 0 0 100 0
0 0 0 282120 134108 5797012 0 0 0 0 1117 577 0 0 100 0
0 0 0 282120 134108 5797012 0 0 0 0 1007 366 0 0 100 0

Which two LVM commands are missing from the following sequence which is used to create a logical volume and make use of it on a Linux system?
pvcreate, ___________, __________, mkfs, mount