CentOS7 入门实战视频课程笔记

Posted 2020-10-19 Bob_C

 

http://zhongcl.blog.51cto.com/1389550/1902252

解决办法：

 登入root

 进入/etc/resolv.conf

 

vim /etc/resolv.conf

 修改内容为下（将DNS地址改为google域名服务器）

nameserver 8.8.8.8 

nameserver 8.8.4.4

扩展：

resolv.conf是DNS域名解析的配置文件，它的格式很简单，每行以一个关键字开头，后接配置参数。resolv.conf的关键字主要有四个，分别是：

nameserver   #定义DNS服务器的IP地址 domain       #定义本地域名 search       #定义域名的搜索列表 sortlist     #对返回的域名进行排序

/etc/resolv.conf的一个示例：

domain test.com search www.test.com test.com nameserver 202.96.128.86 nameserver 202.96.128.166

最主要是nameserver关键字，如果没指定nameserver就找不到DNS服务器，其它关键字是可选的。

 

scp index.html root@192.168.80.100: /root:意思是将刚才下载的index.html文件发送到远程服务器上，目录是root目录

 

 

 

hostname:查看主机名

hostname abc.com:将主机名修改为abc.com但是这种更改只是更改当前的，电脑重启后又恢复原来的。如果要做修改的话：vi /etc/hostname进去修改。

 

nslookup www.baidu.com

 

vi /etc/hosts:可以修改IP地址所对应的域名。

 

ssh 192.168.5.90 :远程登录一个主机

 

vi /etc/resolv.conf:修改DNS的IP地址

 

 

 

--------------------------跟系统相关的命令--------------------------------

reboot:重启服务器

shutdaown -r now

init 6

init 0:关闭服务器

shutdown -h now:马上关机

shutdown -h 20:25:设置关机时间

mount /dev/cdrom /abc:挂载

 

umount /abc:取消挂载

 

df -h:查看挂载的情况

free:查看内存的情况

top:查看cpu的利用率

date:查看日期

cal:查看日历

cal 2014 :查看某一年的日历

 

date 030617002015:将日期设置为2015年的3月6日下午的5点钟

 

rpm -aq:列出系统中安装的所有程序

 

 

 

打印SQL:SELECT a.case_id AS caseNum, b.name AS custName, a.case_amount AS caseAmount, e.name AS case_overdue_name, a.late_days AS lateDays, a.entrust_start_date AS entrustStartDate, a.entrust_end_date AS entrustEndDate, 0 AS case_process, \'\' AS teamName, \'\' AS staffName, a.id AS caseId, a.handin_time AS handin_time, a.permanent_collection, a.temporary_collection, a.case_call_type, (case when a.case_status >=0 and permanent_collection is null then \'未分案\' when a.case_status >= 0 then \'在催\' when a.case_status = -1 then \'出催\' when a.case_status <= -2 then \'流转\' end) as caseStatus, a.case_enter_date,a.case_end_time FROM dic_coll_consume.cf_case_info a, dic_coll_consume.cf_cust_essential_info b, dic_coll_consume.cf_case_stage_type e WHERE a.cust_id = b.id AND a.case_stage_type = e.id  and (a.permanent_collection in (3)  or a.temporary_collection in (3))

 

打印SQL:SELECT a.case_id AS caseNum, b.name AS custName, a.case_amount AS caseAmount, e.name AS case_overdue_name, a.late_days AS lateDays, a.entrust_start_date AS entrustStartDate, a.entrust_end_date AS entrustEndDate, 0 AS case_process, \'\' AS teamName, \'\' AS staffName, a.id AS caseId, a.handin_time AS handin_time, a.permanent_collection, a.temporary_collection, a.case_call_type, (case when a.case_status >=0 and permanent_collection is null then \'未分案\' when a.case_status >= 0 then \'在催\' when a.case_status = -1 then \'出催\' when a.case_status <= -2 then \'流转\' end) as caseStatus, a.case_enter_date,a.case_end_time FROM dic_coll_consume.cf_case_info a, dic_coll_consume.cf_cust_essential_info b, dic_coll_consume.cf_case_stage_type e WHERE a.cust_id = b.id AND a.case_stage_type = e.id  and (a.permanent_collection in (3)  or a.temporary_collection in (3))

 

 

 

打印SQL:SELECT a.case_id AS caseNum, b.name AS custName, a.case_amount AS caseAmount, e.name AS case_overdue_name, a.late_days AS lateDays, a.entrust_start_date AS entrustStartDate, a.entrust_end_date AS entrustEndDate, 0 AS case_process, \'\' AS teamName, \'\' AS staffName, a.id AS caseId, a.handin_time AS handin_time, a.permanent_collection, a.temporary_collection, a.case_call_type, (case when a.case_status >=0 and permanent_collection is null then \'未分案\' when a.case_status >= 0 then \'在催\' when a.case_status = -1 then \'出催\' when a.case_status <= -2 then \'流转\' end) as caseStatus, a.case_enter_date,a.case_end_time FROM dic_coll_consume.cf_case_info a, dic_coll_consume.cf_cust_essential_info b, dic_coll_consume.cf_case_stage_type e WHERE a.cust_id = b.id AND a.case_stage_type = e.id  and (a.permanent_collection in (2698,2704,2705,2707,2708,2709,2710,2716,2719,2720,2717)  or a.temporary_collection in (2698,2704,2705,2707,2708,2709,2710,2716,2719,2720,2717)) 

 

 

 

正常：

打印SQL:SELECT a.case_id AS caseNum, b.name AS custName, a.case_amount AS caseAmount, e.name AS case_overdue_name, a.late_days AS lateDays, a.entrust_start_date AS entrustStartDate, a.entrust_end_date AS entrustEndDate, 0 AS case_process, \'\' AS teamName, \'\' AS staffName, a.id AS caseId, a.handin_time AS handin_time, a.permanent_collection, a.temporary_collection, a.case_call_type, (case when a.case_status >=0 and permanent_collection is null then \'未分案\' when a.case_status >= 0 then \'在催\' when a.case_status = -1 then \'出催\' when a.case_status <= -2 then \'流转\' end) as caseStatus, a.case_enter_date,a.case_end_time FROM dic_coll_consume.cf_case_info a, dic_coll_consume.cf_cust_essential_info b, dic_coll_consume.cf_case_stage_type e WHERE a.cust_id = b.id AND a.case_stage_type = e.id  and (a.permanent_collection in (2698,2704,2705,2707,2708,2709,2710,2716,2719,2720,2717)  or a.temporary_collection in (2698,2704,2705,2707,2708,2709,2710,2716,2719,2720,2717))

 

 

打印SQL:SELECT a.case_id AS caseNum, b.name AS custName, a.case_amount AS caseAmount, e.name AS case_overdue_name, a.late_days AS lateDays, a.entrust_start_date AS entrustStartDate, a.entrust_end_date AS entrustEndDate, 0 AS case_process, \'\' AS teamName, \'\' AS staffName, a.id AS caseId, a.handin_time AS handin_time, a.permanent_collection, a.temporary_collection, a.case_call_type, (case when a.case_status >=0 and permanent_collection is null then \'未分案\' when a.case_status >= 0 then \'在催\' when a.case_status = -1 then \'出催\' when a.case_status <= -2 then \'流转\' end) as caseStatus, a.case_enter_date,a.case_end_time FROM dic_coll_consume.cf_case_info a, dic_coll_consume.cf_cust_essential_info b, dic_coll_consume.cf_case_stage_type e WHERE a.cust_id = b.id AND a.case_stage_type = e.id  and (a.permanent_collection in (3)  or a.temporary_collection in (3))