First, we look at Netease Linux operation and maintenance engineers recruitment requirements:
[Post] the definition of a senior systems engineer (application operation and maintenance)
[Post] 15K-25K salary
【description of job】
1. The construction company responsible for operation and maintenance system, organization and business systems online mobile APP and self-built private cloud monitoring, maintenance, and promote automation operation and maintenance;
2. To establish and improve the company's operation and maintenance monitoring system and event handling mechanism to ensure the stable operation of the business;
3. with the product development team to deploy applications and services, testing, tuning, operations, etc., and suggesting adjustments for the operation of the product;
4. organize the operation and maintenance of various types of documents, precipitation experience.
【Job Requirements】
1. Key Bachelor degree or above, Linux Internet company more than 2 years experience in operation and maintenance;
2. Proficient in building and maintaining zabbix monitoring system, to develop custom scripts;
3. Familiar Nginx / Apache / Tomcat and other Web application server deployment, optimization;
4. Familiar with shell, perl and other scripting languages and have a certain ability to develop, python and other languages can be used for simple operation and maintenance tools and page development;
The skilled automation configuration tool, such as febric, saltstack the like;
6. skill in using tools for network troubleshooting, familiar iptables, vpn other network tools;
7. A virtualized environment, public cloud platform experience preferred.
The following is Netease Linux operation and maintenance engineers interview Zhenti:
1.SDRAM、DDR2、DDR3…
答：
1, (Synchronous Dynamic Random Access Memory ) synchronous dynamic random access memory. SDRAM in one clock cycle of data transmission only once, it is the rise of the clock
data transmission.
2, (Double Data Rate) double data rate synchronous dynamic random access memory. DDR memory is a clock cycle data is transmitted twice, each capable of transmitting a rising period and a falling period of the clock
time data.
DDR2 (Double Data Rate 2). It is with the previous generation DDR memory technology standard biggest difference is that, although the same is adopted in the clock rise / fall delay while the basic data transmission side
style, but DDR2 memory, however, has twice the previous generation DDR memory pre-fetch capability (ie: 4bit pre-read data). In other words, DDR2 memory per clock can be read at a speed of 4 times the external bus / write data
, and can be 4 times the speed of the internal control bus operation.
And DDR3 prefetch is 8bit, so the burst transfer cycle (Burst Length, BL) 8 is also secured.
2. Which of the following commands can not exit the vi editor :: x,: q,: q
,:! Bye A: The last one, namely: BYE
:. The X-(write the file and quit only if the file is modified written, and updates the file modification time, otherwise it will not update the file modification time).
: q (quit general, if there is a write operation, the prompt)
:! q (force quit, if there is a write operation is not saved)
3. Which of the following protocols have both TCP UDP-: telnet, SMTP, DNS ...
A: the Telnet (TCP)
the SMTP (TCP)
DNS (tcp / udp)
DNS general use UDP, when synchronizing the primary and secondary DNS name server using the TCP protocol
4 to have the following several routes to the same destination, static, RIP, OSPF, and asked which a data packet through.
A: The default use a static route configured station interface and a static route configuration of the next hop address AD is 1, selected from static.
Annex:
Routing Default Source AD
connection Interface 0
1 Static Routing
EIGRP 90
IGRP 100
the OSPF 110
the RIP 120
External EIGRP 170.
Unknown 255 (This route will never be used)
Second, fill in the blank
1.SAN's Chinese name is _ a storage area network (Storage Area Network) _______; NAS Chinese name is ___ network storage device (NAS: Network Attached Storage).
2. In addition to writing three types of linux Unix system __Solaris ____, __ FreeBSD _____, _ AIX______.
3. If there are three documents ............, with a simple command to merge a document ___cat file1.out file2.out file3.out> file4.out ______.
4. matching string, c c [?]
A: The title should not be a complete, braces any character
5. an IP address 192.168.48.10, mask of 255.255.255.128, a subnet in which it is __192.168.48.0 ________, the broadcast
address is ______ 192.168.48.127 ________, valid host IP address range from ______ 192.168.48 .1 to _________ ___ 192.168.48.126 _____________.
6. Review the command TCP connection ____netstat______.
7. In the OSI model, HTTP protocol works __7__ first layer, the second switch operates _1-2 ___ layer. (This question is not precise enough, think back to fill two layers, 1-2 layers are not wrong)
8. Write some mature virtual machine technology ____ VMWare, __ XEN, Bochs ______________. (Personally I think that the more filled out, the more you can demonstrate extensive knowledge, plus the feelings of points)
Third, the short answer
1.32 operating system and 64-bit operating system differences, and give their advantages and disadvantages.
A: Advantages: may be a wider range of integer arithmetic; can support more memory. As support for more addressable space is greater than 4GB. Support for larger virtual memory 16TB, support more page file
512TB, support more system cache 1TB. Support higher color quality (264 2)
Disadvantages: The disadvantage is the difference between backward compatibility to support hardware drivers less. Less support applications. It requires hardware support.
2. SSDs and traditional hard drive What is the difference, and explain their advantages and disadvantages.
A: A little: shock resistance, small mechanical point of failure. Small noise. Heat, small size. Read and write speed.
Disadvantages: the capacity of small and expensive. Data recovery is poor.
3. Multi-core CPU and single-core CPU advantages and disadvantages, whether all programs running on multi-core CPU speed faster? why?
Answer: It is not.
By a single-core processor, increased multi-core processor, clocked if the same words, IPC (the number of instructions executed per clock cycle) can theoretically double the power it up to theoretically double the work because linear increase in consumption. However, some programs only run on a single Nucleation.
4. give you six 150G hard drive, lists the RAID arrangement, which way the largest capacity, and interpretations.
A: The six drives must not make use of RAID01 arrays. The maximum can only do RAID0: 4 * Capacity 150
RAID5: Capacity 150 * (6-1)
RAID0 + 1: Capacity 150 * (6/2)
So the answer is RAID5
5. There is a web server, and one day a customer complaints on a website is very slow, if you are an administrator, how do you find out why. Assuming the server has any operating system and software.
A: 1, the first state detection server, hardware failures and system failures excluded machinery troubleshooting
2, check the status of the underlying network (including the Internet case, the PING packet delay, traffic conditions) to troubleshoot the device and network card, network failure.
3. Check the operation of WEB server software (concurrent connections, software configuration services, database connections, etc.) exclude the application service failure.
Fourth, the program title (The answer is not complete)
1. a program run once every 5 minutes, arrive at a result run, save the document in the format
2008-06-01 00:05:00 1120
(1) on a daily 23:56 access the document, save the operation results to the document day,
[such as: /..../... ../ 20080601]
(2) the sum of the statistical results of running a day.
Design a plan and program to achieve.
2. Games, (people, performance)
to save the format for each line a score, as the first name, the second as a result. Such as 24-Jim
(1)
(2)
(3) statistical everyone's grade point average (GPA = total score / total number of participants item), press the grade point average from high to low.
Fifth, the reasoning questions
1. In a Pacific island inhabited by natives, they do not like outsiders to disturb. One day an explorer came to the island, caught natives, natives of the priests told explorer, he had the opportunity to stay in the interim before
the next sentence, if this statement is true, he will be burned to death, If this statement is false, he will be Wumafenshi , how can poor explorers survive? And explain.
A: I will be crowd favorite
if it is the truth, visitors will be burned to death, and will not be crowd favorite, so visitors said is a lie! contradiction!
If it is a lie, visitors will be crowd favorite, did as he said, so visitors said is the truth! contradiction!
In this way, we can not tell visitors said is true! People on the island will not be able to perform their rules!
Six essay questions
1. the following situations, those are the most unpredictable? What can be avoided? How will you face?
(1) The boss called you into his office and let you in charge of a new project, and remind you the next few weeks will be very busy.
A: unpredictable. But the planned arrangements currently working well in hand, and accept the new program is a test of their own.
(2) a friend sent you an email, introduce a useful website, you took a few minutes to visit the website.
A: avoided. Before browsing this site thoroughly understand what is worth spending some time to see.
(3) a customer called me, you want to rush to their company.
A: avoided. If the work can be done through the network, run the world do in the past.
(4) The boss wants you to complete certain tasks before work.
A: unpredictable. Try to complete, if it is not completed, the leadership would like to explain the reasons obscure, for his understanding.
(5) you must immediately put down the work at hand, buy paper cups, paper cups have been found since run out, and after 10 minutes of the meeting will be used.
A: avoided. Some consumables can be of some proper preparation, do not let these tedious work interrupted by more important work at hand.
2. Do you think the key qualities of a good game operations and maintenance engineer must have what? From the order to explain the main press times.
A: 1, take the initiative optimistic, positive attitude
2, attentive and anti-stress
3, a wealth of knowledge and strong communication skills
4, always a cool head
5, integrity
