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随机应变 ABCD: Always Be Coding and … : хороший
It is possible to specify up to 8 levels in the error log up to which level errors should be recorded. set to “LogLevel” to specify.
LogLevel to record.
The level that can be set are as follows.
Level Meaning
A serious error that the emerg server can not run.
-Errors: More serious than alert crit
-Crit; Serious error
-Error: Error
-Warn: Warning
-Notice: Notification message
-Info: Server information, information for debug debugging.
egrep [option][search string pattern] filename
Search for files with a search string pattern and a command to output matching lines.
Search for [File] with [Search string pattern] and output matching lines.
You can use regular expressions more advanced than grep.
まず適すとファイルを作ります。
yahoo.txt
1 8411 東証1部 (株)みずほフィナンシャルグループ 03/20 175.5 +0.75% +1.3 106,216,600 掲示板 2 5020 東証1部 ＪＸＴＧホールディングス(株) 03/20 542.9 +0.37% +2 42,028,800 掲示板 3 8306 東証1部 (株)三菱ＵＦＪフィナンシャル・グループ 03/20 573.3 -0.26% -1.5 33,412,300 掲示板 4 3765 東証1部 ガンホー・オンライン・エンターテイメント(株) 03/20 405 +5.74% +22 31,808,200 掲示板 5 4347 東証JQS ブロードメディア(株) 03/20 94 +9.30% +8 29,353,800 掲示板 6 4755 東証1部 楽天(株) 03/20 1,011 +4.12% +40 22,479,800 掲示板 7 9973 東証JQS (株)小僧寿し 03/20 62 +44.19% +19 18,652,400 掲示板 8 8604 東証1部 野村ホールディングス(株) 03/20 409.9 -2.24% -9.4 18,591,800 掲示板 9 3092 東証1部 (株)ＺＯＺＯ 03/20 2,025 +1.25% +25 18,435,700 掲示板 10 4565 マザーズ そーせいグループ(株) 03/20 1,421 +15.91% +195 18,249,700 掲示板
続いて、egrep -i
[vagrant@localhost tests]$ egrep -i "グループ" yahoo.txt 1 8411 東証1部 (株)みずほフィナンシャルグループ 03/20 175.5 +0.75% +1.3 106,216,600 掲示板 3 8306 東証1部 (株)三菱ＵＦＪフィナンシャル・グループ 03/20 573.3 -0.26% -1.5 33,412,300 掲示板 10 4565 マザーズ そーせいグループ(株) 03/20 1,421 +15.91%+195 18,249,700 掲示板
ほう。
-n：文字列長が 0 より大なら真
#!/bin/sh index="hoge" if [ -n $index ]; then echo "文字列長が0より大です" fi
[vagrant@localhost tests]$ sed -i ‘s/\r//’ test.sh
[vagrant@localhost tests]$ ./test.sh
文字列長が0より大です
#!/bin/sh index="" if [ -n $index ]; then echo "文字列長が0より大です" fi
[vagrant@localhost tests]$ sed -i ‘s/\r//’ test.sh
[vagrant@localhost tests]$ ./test.sh
文字列長が0より大です
あれええええええええええええええええええ？？
ERROR 1068 (42000): Multiple primary key defined
複合primary keyで書こうとするとエラーになった。
create table hoge( submit_no int not null, seq_no int not null, report_file_name varchar(128), create_userid char(20) not null, create_date date not null, update_userid char(20), update_date date, primary key(submit_ms_no, seq_no) );
mysql> describe hoge;
+———————-+————–+——+—–+———+——-+
| Field | Type | Null | Key | Default | Extra |
+———————-+————–+——+—–+———+——-+
| submit_no | int(11) | NO | PRI | NULL | |
| seq_no | int(11) | NO | PRI | NULL | |
| report_img_file_name | varchar(128) | YES | | NULL | |
| create_userid | char(20) | NO | | NULL | |
| create_date | date | NO | | NULL | |
| update_userid | char(20) | YES | | NULL | |
| update_date | date | YES | | NULL | |
+———————-+————–+——+—–+———+——-+
7 rows in set (0.00 sec)
なるほど。。create文がそもそも違うのね。
一つのテーブルで複数のprimary keyって設定できるの？
submit_noとseq_noでprimary keyを設定するとします。
create table rep_image_info( submit_no int not null primary key, seq_no int not null primary key, report varchar(128), create_user char(20), create_date date, update_user char(20), update_date date );
この場合、submit_noとseq_noの組み合わせに対して主キーを持つようです。なるほどにゃー
よって、二つでだけでなく、三つ、四つのprimary keyもあるわけですね。
SLA is an abbreviation of Service Level Agreement, which is an agreement on the level of service (definition, scope, content, achievement goals, etc.) established between the provider of the service and its users. This is a statement to the extent that the service provider can guarantee the quality to the contractor.
SLAs are often used mainly for communication services, cloud services, rental servers, etc. We define service definition and guarantee items such as communication speed and upper limit of use stop time, and if the service quality falls below the guarantee value of SLA, reduction of charge will be performed.
ELBでアクセスログが取得できる。
2014-03-07T07:25:38.285777Z elber 130.0.237.XX:37522 172.31.4.218:80 0.000066 0.00105 0.000037 404 404 0 570 "GET http://54.249.27.XX:80/actus4/ HTTP/1.1" 2014-03-07T07:26:43.731149Z elber 77.50.22.XXX:53477 172.31.4.218:80 0.000053 0.000866 0.000053 200 200 0 10 "GET http://54.249.27.XX:80/ HTTP/1.0" 2014-03-07T07:26:44.410747Z elber 77.50.22.XXX:53656 172.31.4.218:80 0.000052 0.000853 0.000039 404 404 0 168 "GET http://54.249.27.XX:80/foltia/ HTTP/1.0" 2014-03-07T07:26:45.084730Z elber 77.50.22.XXX:53839 172.31.4.218:80 0.000061 0.000874 0.000035 404 404 0 168 "GET http://54.249.27.XX:80/epgrec/do-record.sh HTTP/1.0" 2014-03-07T07:28:12.386207Z elber 189.206.75.XX:64289 172.31.4.218:80 0.000062 0.000924 0.000035 404 404 0 168 "GET http://54.249.27.XX:80/manager/html HTTP/1.1"
問題は、項目。
timestamp
The time accessed by the Client. UTC time, recorded in ISO 8601 format.
2014-02-15T23: 39: 43. 945958 Z
Name of ELB
ELB Name: test-loadbalancer
Client
Port Client IP address and port number
192.168.131.39.2817
Backend
port IP address and port number of the instance to which communication was distributed by ELB. This will tell you which server it was assigned to 10.0.0.0:80
request_processing_time
The time between the ELB receiving a request from the client and sending the request to the instance
0.000073
backend_processing_time
The time it takes for the ELB to send a request to an instance and the instance returns a response.
0.001048
response_processing_time
The time from when the ELB receives a response from an instance to when it returns a response to the client.
0.000057
elb_status_code
response status code.
200
backend_status_code
Response status code of the instance to which the ELB sent the request.
200
received_bytes
Size of received request (bytes)
0
sent_bytes
Size of sent request (bytes)
29
request
request from a client
“GET http://www.example.com:80/HTTP/1.1”
How to investigate user agent?
As an example, the user agent for IE9 is described as follows.
Mozilla / 5.0 (compatible;MSIE 9.0; Windows NT 6.1; Trident/5.0)
Application name
It corresponds to the “Mozilla” part. It is used in the sense that it has the function of the type of browser or its application.
Application Version
In the “5.0” part after Mozilla, it indicates the version of the application.
Platform token
It corresponds to the “Windows NT 6.1” part. It will be the display about OS.
Version Token
It corresponds to the part of “MISE 9.0”.Displaying browser version.
Compatibility Flags
It corresponds to the “Compatible” part. It shows the compatibility with Internet Explore.
Rendering engine
It corresponds to the part of “Trident/5.0”. Shows software that causes the browser to display the requested content.
Internet Explore
ver.11
Mozilla / 5.0 (Windows NT 6.3; ARM; Trident / 7.0; Touch; MALNJS; rv: 11.0) like Gecko
ver.10
Mozilla / 5.0 (compatible; MSIE 10.0; Windows NT 6.2; WOW 64; Trident / 6.0)
Chrome
Mozilla / 5.0 (Windows NT 5.1) AppleWebKit / 535.11 (KHTML, like Gecko) Chrome / 17.0.963.79 Safari / 535.11
Firefox
Mozilla / 5.0 (Windows NT 6.1; rv: 11.0) Gecko / 20100101 Firefox / 11.0
Safari
Mozilla / 5.0 (Macintosh; U; Intel Mac OS X; en-jp) AppleWebKit / 523.12 (KHTML, like Gecko) Version / 3.0.4 Safari / 523.12
Android
Mozilla / 5.0 (Linux; Android 4.4.2; 302KC Build / 101.0.2c00) AppleWebKit / 537.36 (KHTML, like Gecko) Version / 4.0 Chrome / 30.0.0.0 Mobile Safari / 537.36 YJApp-ANDROID jp.co.yahoo.android. ybrowser / 1.7.5
なるほど、内容よく見ると、どのブラウザか一発でわかりますね。まあ、一般的にユーザーエージェントは偽装されるのであまり意味ないかもしれませんが。そういえば、IPって偽装できるんでしょうか？？？ Chrome Extensionで、Hotspot Shieldを使えば偽装できるようですが。。
What is HTTP 460 on ELB
The load balancer received a request from a client, but the client closed the connection with the load balancer before the idle timeout expired.
Check if the client timeout period is longer than the load balancer idle timeout period. Before the client timeout period expires, make sure that target returns a response to the client, or if the client supports it, increase the client timeout period to match the load balancer idle timeout.
The 301 redirect is “permanent redirect” and “permanent transfer”, while the 302 redirect is “temporary redirect” and “temporary transfer”.
Consider that a URL set to 301 redirect will not appear in the index. However, the 301 redirect takes over the information of the transfer source (old URL) to the transfer destination (new URL).