I just found out that i could not access my wordpress today, i checked the server, everything looked good. i restarted the server, it’s still slow, there is no error. I decided to do a debug using the following command: cd /www/myswebsite.com/httpdocs/ strace php index.php I see my script stopped at sendmmsg(6, {{{msg_name(0)=NULL, msg_iov(1)=[{“-\265\1\0\0\1\0\0\0\0\0\0\24tech-banker-service”…, 42}], msg_controllen=0, msg_flags=MSG_DONTROUTE|MSG_DONTWAIT|MSG_FIN|MSG_SYN|MSG_ERRQUEUE|MSG_NOSIGNAL|MSG_FASTOPEN|0x6a80010}, 42}, {{msg_name(0)=NULL, msg_iov(1)=[{“\207E\1\0\0\1\0\0\0\0\0\0\24tech-banker-service”…, 42}], msg_controllen=0, msg_flags=MSG_OOB|MSG_DONTROUTE|MSG_CTRUNC|0x10}, 42}}, 2, MSG_NOSIGNAL) = 2 poll([{fd=6, events=POLLIN}], 1, 5000) = 1 ([{fd=6, revents=POLLIN}]) ioctl(6, FIONREAD, [58]) = 0 recvfrom(6, “-\265\201\200\0\1\0\1\0\0\0\0\24tech-banker-service”…, 2048, 0, {sa_family=AF_INET, sin_port=htons(53), sin_addr=inet_addr(“213.133.99.99”)}, [16]) = 58 poll([{fd=6, events=POLLIN}], 1, 4999) = 1 ([{fd=6, revents=POLLIN}]) ioctl(6, FIONREAD, [135]) = 0 recvfrom(6,Read More →

The folder /etc/cron.d/ is used to store all cronjobs, the cronjob is saved on the file , the format is: minute hour day month dayofweek username command_to_run. There might some problems – the syntax is not correct , and the result is that the whole file will be ignore.  I don’t know how to check the syntax , but i can watch to the syslog to see if there is any error. After we edit the file in crontab , the system will reload the cronjob, if there is any error it will throw an error in syslog. So i setup this before editing theRead More →

smartctl is a nice tool to check your hard disk health – it will let you know how many hours your disk have been running , the hard disk serial number, temperature … by default smartctl is not installed by default, it’s in smartmontools package. To make it ready to use, you must install smartmontools apt-get install smartmontools After you install smartmontools you can run this command to check your hard disk health: smartctl –xall /dev/sda Here is a sample: smartctl 6.5 2016-01-24 r4214 [x86_64-linux-4.4.0-28-generic] (local build) Copyright (C) 2002-16, Bruce Allen, Christian Franke, www.smartmontools.org === START OF INFORMATION SECTION === Model Family: Toshiba 3.5″Read More →

The Diamond operator is almost exclusively used in a while-loop. It allows us to iterate over the rows in all the files given on the command line. Diamond – using $_, the default variable We can make the above example even more compact by remembering that certain operation in Perl will use $_, the default variable of Perl, if no explicit variable is given. use strict; use warnings; while (<>) { print if /perl/; }  Read More →

Check this out: https://www.cloudflare.com/technical-resources/#mod_cloudflare Option 1: Installation from Packages Download the appropriate package to your web server and install it using your operating system’s ‘rpm’ or ‘dkpg’ commands. For RedHat / CentOS / CloudLinux: # yum install glibc.i686 # rpm -i mod_cloudflare-elX.latest.rpm For Debian / Ubuntu: # dpkg -i mod_cloudflare-XXXXX.latest.deb RHEL/CentOS/CloudLinux RHEL/CentOS/CloudLinux 7 (64-bit) RHEL/CentOS/CloudLinux 6 (64-bit) Debian Debian 8 (64-bit) Debian 7 (64-bit) Ubuntu Ubuntu 16.04 (64-bit) Ubuntu 15.10 (64-bit) Ubuntu 15.04 (64-bit)Ubuntu 14.04 (64-bit) Ubuntu 12.04 (64-bit)Read More →

AH00526: Syntax error on line 55 of /etc/apache2/apache2.conf: Invalid command ‘LockFile’, perhaps misspelled or defined by a module not included in the server configuration Action ‘start’ failed. Solutions: Replacing this line LockFile ${APACHE_LOCK_DIR}/accept.lock with this one Mutex file:${APACHE_LOCK_DIR} default in /etc/apache2/apache2.conf solved the problem.Read More →