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How to set up sendmail on CentOS?

It is said postfix is the most popular mail server now. However, postfix is not installed on my VPS. Instead, sendmail is installed by default although I never started the service before. So I decide to use sendmail as the

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sql syntax memo

mysql> select table1.id1,table1.field1,table2.id2,table2.field2 from table1, table2; mysql> select table1.id1,table1.field1,table2.id2,table2.field2 from table1  join table2; mysql> select table1.id1,table1.field1,table2.id2,table2.field2 from table1 inner join table2; The above three statements return the same result: the Cartesian product of table1 and table2 If you use outer

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how to compress mysql databases?

Here we talk about enabling compression for mysql innodb tables. Follow the following steps to compress the tables and save disk space. 1 enable innodb_file_per_table add a line “innodb_file_per_table” under [mysqld] in /etc/my.cnf. This will make databases use their own

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What databases/tables does Sentora use?

I accidentally deleted some databases Sentora uses to store its system data, which leads to the inaccessibility of Sentora panel. To recover   corrupted or deleted Sentora system databases/tables, you should first know what databases/tables it uses. During installation, Sentora

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bash memo

I always forget the syntax of if…then..else…fi clauses if test 1 -gt 0 then echo yes fi will produce the error:-bash: syntax error near unexpected token `fi’ if test 1 -gt 0 then echo yes fi will produce the same

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xl2tpd Maximum retries exceeded for tunnel

I could not connect to my l2tp vpn. It took me some time to find the locations of related logs. Open /var/log/messages and I find the xl2tpd error:  “xl2tpd[xxxx]: Maximum retries exceeded for tunnel xxx. Closing.” Searching the error message

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where are l2tp vpn logs in CentOS?

I am setting up an l2tp vpn using openswan(libreswan) and xl2tpd. Unfortunately, the vpn does not work. So I want to debug the problem. First, I should know where the l2tp vpn logs are. Searching the internet for where ipsec

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why my cron job is not running?

I have got  some problem running a cron job. Although I’ve researched the usage of cron job earlier, I still cannot make my crob job run as expected. I used crontab -e to add a new crob job as follows:

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Script timeout passed, if you want to finish import, please resubmit same file and import will resume.

Using phpMyAdmin to import large database often triggers the error:”Script timeout passed, if you want to finish import, please resubmit same file and import will resume.” It seems the same error as you execute a time-consuming php file. You know

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what characters can appear in the result of get ideas for adwords keyword planner?

To get new keywords based on a feed keyword using adwords keyword planner, you click the “Search for new keywords using a phrase,website or category” and input a feed keyword in the “Your product or service” box, then click the

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