You use the host command to find out about host name WAYOUT:
Which two statements are true?
Which three statements are true about the mount command?
References:
Users complain that system performance is unacceptable when using a specific application service running on a multiprocessor service.
You have established from the storage team that disk response times have not increased, so you can discount there being an I/O problem.
You run vmstat to look at CPU activity and notice high average disk times on the multiprocessor system and an average run queue of zero.
You require more detail about each CPU from which the vmstat figures are derived, to investigate if the load is distributed evenly across all CPUs.
Which three commands provide more detailed information about CPU load distribution?
C: A useful command to get CPU related stats is mpstat. Here is an example output:
# mpstat -P ALL 5 2
Linux 2.6.9-67.ELsmp (oraclerac1) 12/20/2008
10:42:38 PM CPU %user %nice %system %iowait %irq %soft %idle intr/s
10:42:43 PM all 6.89 0.00 44.76 0.10 0.10 0.10 48.05 1121.60
10:42:43 PM 0 9.20 0.00 49.00 0.00 0.00 0.20 41.60 413.00
10:42:43 PM 1 4.60 0.00 40.60 0.00 0.20 0.20 54.60 708.40
etc.
D: When called, the grand-daddy of all memory and process related displays, vmstat, continuously runs and posts its information. It takes two arguments:
# vmstat <interval> <count>
<interval> is the interval in seconds between two runs. <count> is the number of repetitions vmstat makes. Here is a sample when we want vmstat to run every five seconds and stop after the tenth run. Every line in the output comes after five seconds and shows the stats at that time.
# vmstat 5 10
procs -----------memory---------- ---swap-- -----io---- --system-- ----cpu----
r b swpd free buff cache si so bi bo in cs us sy id wa
0 0 1087032 132500 15260 622488 89 19 9 3 0 0 4 10 82 5
0 0 1087032 132500 15284 622464 0 0 230 151 1095 858 1 0 98 1
0 0 1087032 132484 15300 622448 0 0 317 79 1088 905 1 0 98 0
... shows up to 10 times.
The output shows a lot about the system resources.
E: sar stands for System Activity Recorder, which records the metrics of the key components of the Linux system---CPU, Memory, Disks, Network, etc.---in a special place: the directory /var/log/sa.
The simplest way to use sar is to use it without any arguments or options. Here is an example:
# sar
Linux 2.6.9-55.0.9.ELlargesmp (prolin3) 12/27/2008
12:00:01 AM CPU %user %nice %system %iowait %idle
12:10:01 AM all 14.99 0.00 1.27 2.85 80.89
12:20:01 AM all 14.97 0.00 1.20 2.70 81.13
12:30:01 AM all 15.80 0.00 1.39 3.00 79.81
12:40:01 AM all 10.26 0.00 1.25 3.55 84.93
Incorrect:
Not A: iostat is for I/O
You want sendmail to deliver mail for these users:
John.smith@acme.comto mailbox jsmith1
John.smith@foo.comto mailbox jsmith2
John.smith@bar.comto mailbox jsmith3
In which sendmail configuration database can this requirement be defined?
/etc/mail/virtusertable
This database file maps mail addresses for virtual domains and users to real mailboxes. These mailboxes can be local, remote, aliases defined in /etc/mail/aliases, or files. This allows multiple virtual domains to be hosted on one machine.
The following example demonstrates how to create custom entries using that format:
root@example.com root
postmaster@example.com postmaster@noc.example.net
@example.com joe
The user scott tries to create a directory hierarchy under a specific directory location and encounters an error:
Which command must scott use to create the directory hierarchy successfully? (Choose the best answer.)
