Posts tagged server
If you decided to use Google as your mail server and already set up it in a way like:
- Set the SMTP server name to smtp.gmail.com
- Set the username to your google email address
- Enter your password
- Set SMTP Port to 465
- Set SMTP Encryption to TLS
yet when I tried to send email I was receiving “internal server error ” msgs.
In the error log I see “Premature header…”
After spending hours on research I found that on your server you should have outgoing port 465 not blocked by the firewall.
MySQL tables can crash quite easily, especially when your server unexpectedly shuts down or crashed, or when you're forced to copy data around when it's still being accessed.
Luckily, there's a simple command to automatically check, repair and optimize all tables in all databases when you're running a MySQL server on Linux / Unix / BSD.
mysqlcheck -u root -p --auto-repair --check --optimize --all-databases
That's all there is to it!
Are you looking to create a website and have your own webhost? It is very simple but the first step is to find a dependable webhost company. We tried over 10 webhost companies (Servage, GoDaddy, Hostmonster, Blue host and may more) in the past 8 years and found the most affordable and dependable was DreamHost
There is nothing to loose you always have your 97 days money back grantee but further if you use our promo coupon you can take 90 USD OFF just use promotional discount coupon code:
Below is a table comparing popular webhosts and any hidden limtations they have. If you have updates to this please comment.
|Price Promo 1yr||$107.4-90=$17.4 /first year||Adhoc 5.95$x12=$71.4||$6.64×12=$79.68|
|Host Unlmited Domains||Yes||Yes||Yes|
|Hosting Space||Unlimited||“Unlimited” but if high your account will be suspended||150GB|
|SSH Access||By Default||Need to send ID||Can be requested no ID needed|
|CPU Limit||No Limitation||60Sec then Site suspended||No Limitation|
|First Yr Domain Registration Free||Yes||Yes||No|
|Tech Support||Chat, Email Ticket system(response time: 1-24hours),Phone: only call back||Phone, Chat, Ticket(Response time 1-24 Hours)||Phone,Ticket(slow 1 Day response time)|
|Install Custom PHP||Yes Simple see article here||No||No|
|Max File Upload Size||7MB, unlimited with Custom PHP install||2MB, can be increased with copying php to all folders, still limited with CPU time limit||7MB|
|Can host Adult Content||Yes||No||Yes|
|Loading speed for a 64kb website size||2-3 Seconds performance is stable since dreamhost upgraded to new servers||2-3 Seconds, performance was stable||5-6 Seconds|
|Midnight Commander||Installed by default||Not installed and can not install it||Not sure|
General Information [ ^ ]
.htaccess Definition1 [ ^ ]
Apache server software provides distributed (i.e., directory-level) configuration via Hypertext Access files. These
htaccess files enable the localized fine-tuning of Apache’s universal system-configuration directives, which are defined in Apache’s main configuration file. The localized
htaccess directives must operate from within a file named
htaccess. The user must have appropriate file permissions to access and/or edit the
htaccess file. Further,
htaccess file permissions should never allow world write access — a secure permissions setting is “644”, which allows universal read access and user-only write access. Finally,
htaccess rules apply to the parent directory and all subdirectories. Thus to apply configuration rules to an entire website, place the
htaccess file in the root directory of the site.
Commenting .htaccess Code [ ^ ]
Comments are essential to maintaining control over any involved portion of code. Comments in
htaccess code are fashioned on a per-line basis, with each line of comments beginning with a pound sign
#. Thus, comments spanning multiple lines in the
htaccess file require multiple pound signs. Further, due to the extremely volatile nature of htaccess voodoo, it is wise to include only alphanumeric characters (and perhaps a few dashes and underscores) in any
Good thing to have ssh access set up for both webhosts.
An easy way of migrating the databases especially when it is a big database and it size is over what you have in PhpMyAdmin setup:
Login to the new server with ssh and type:
mysqldump -h oldhost -u oldusername -poldpassword olddbname | mysql -h newhost -u newusername -pnewpassword newdbname
Note: if this did not work check your passwords or check if your new server is white listed (remote mysql access) on the old server.
Below is a list of common SSH commands that can be very useful I will be updating this as I suffer through my hosting (Article provided by WebHostGear.com):
Common SSH Commands or Linux Shell Commands,
ls : list files/directories in a directory, comparable to dir in windows/dos.
ls -al : shows all files (including ones that start with a period), directories, and details attributes for each file.
ls -alF: shows all files and its owners
cd : change directory · · cd /usr/local/apache : go to /usr/local/apache/ directory
cd ~ : go to your home directory
cd – : go to the last directory you were in
cd .. : go up a directory cat : print file contents to the screen
cat filename.txt : cat the contents of filename.txt to your screen
chmod: changes file access permissions
The set of 3 go in this order from left to right:
USER – GROUP – EVERONE
1 = –X Execute only
2 = -W- Write only
3 = -WX Write and execute
4 = R– Read only
5 = R-X Read and execute
6 = RW- Read and write
7 = RWX Read, write and execute
chmod numberpermissions filename
chmod 000 : No one can access
chmod 644: Usually for HTML pages
chmod 755: Usually for CGI scripts
chown: changes file ownership permissions
The set of 2 go in this order from left to right:
USER – GROUP
chown root myfile.txt : Changes the owner of the file to root
chown root.root myfile.txt : Changes the owner and group of the file to root
chown -Rf Username Foldername : Changes the owner of a directory and all files in it
tail : like cat, but only reads the end of the file
tail /var/log/messages : see the last 20 (by default) lines of /var/log/messages
tail -f /var/log/messages : watch the file continuously, while it’s being updated
tail -200 /var/log/messages : print the last 200 lines of the file to the screen
more : like cat, but opens the file one screen at a time rather than all at once
more /etc/userdomains : browse through the userdomains file. hit Spaceto go to the next page, q to quit
pico : friendly, easy to use file editor
pico /home/burst/public_html/index.html : edit the index page for the user’s website.
File Editing with VI ssh commands
vi : another editor, tons of features, harder to use at first than pico
vi /home/burst/public_html/index.html : edit the index page for the user’s website.
When in the vi program you can use the following useful commands, you will need to hit SHIFT + : to go into command mode
:q! : This force quits the file without saving and exits vi
:w : This writes the file to disk, saves it
:wq : This saves the file to disk and exists vi
:LINENUMBER : EG :25 : Takes you to line 25 within the file
:$ : Takes you to the last line of the file
:0 : Takes you to the first line of the file
grep : looks for patterns in files
grep root /etc/passwd : shows all matches of root in /etc/passwd
grep -v root /etc/passwd : shows all lines that do not match root
ln : create’s “links” between files and directories
ln -s /usr/local/apache/conf/httpd.conf /etc/httpd.conf : Now you can edit /etc/httpd.conf rather than the original. changes will affect the orginal, however you can delete the link and it will not delete the original.
last : shows who logged in and when
last -20 : shows only the last 20 logins
last -20 -a : shows last 20 logins, with the hostname in the last field
w : shows who is currently logged in and where they are logged in from.
who : This also shows who is on the server in an shell.
netstat : shows all current network connections.
netstat -an : shows all connections to the server, the source and destination ips and ports.
netstat -rn : shows routing table for all ips bound to the server.
top : shows live system processes in a nice table, memory information, uptime and other useful info. This is excellent for managing your system processes, resources and ensure everything is working fine and your server isn’t bogged down.
top then type Shift + M to sort by memory usage or Shift + P to sort by CPU usage
ps: ps is short for process status, which is similar to the top command. It’s used to show currently running processes and their PID.
A process ID is a unique number that identifies a process, with that you can kill or terminate a running program on your server (see kill command).
ps U username : shows processes for a certain user
ps aux : shows all system processes
ps aux –forest : shows all system processes like the above but organizes in a hierarchy that’s very useful!
touch : create an empty file
touch /home/burst/public_html/404.html : create an empty file called 404.html in the directory /home/burst/public_html/
file : attempts to guess what type of file a file is by looking at it’s content.
file * : prints out a list of all files/directories in a directory
du : shows disk usage.
du -sh : shows a summary, in human-readble form, of total disk space used in the current directory, including subdirectories.
du -sh * : same thing, but for each file and directory. helpful when finding large files taking up space.
wc : word count
wc -l filename.txt : tells how many lines are in filename.txt
cp : copy a file
cp filename filename.backup : copies filename to filename.backup
cp -a /home/burst/new_design/* /home/burst/public_html/ : copies all files, retaining permissions form one directory to another.
cp -av * ../newdir : Copies all files and directories recurrsively in the current directory INTO newdir
mv : Move a file command
mv oldfilename newfilename : Move a file or directory from oldfilename to newfilename
rm : delete a file
rm filename.txt : deletes filename.txt, will more than likely ask if you really want to delete it
rm -f filename.txt : deletes filename.txt, will not ask for confirmation before deleting.
rm -rf tmp/ : recursively deletes the directory tmp, and all files in it, including subdirectories. BE VERY CAREFULL WITH THIS COMMAND!!!
TAR: Creating and Extracting .tar.gz and .tar files
tar -zxvf file.tar.gz : Extracts the file
tar -xvf file.tar : Extracts the file
tar -cf archive.tar contents/ : Takes everything from contents/ and puts it into archive.tar
gzip -d filename.gz : Decompress the file, extract it
ZIP Files: Extracting .zip files shell command
Firewall – iptables commands
iptables -I INPUT -s IPADDRESSHERE -j DROP : This command stops any connections from the IP address
iptables -L : List all rules in iptables
iptables -F : Flushes all iptables rules (clears the firewall)
iptables –save : Saves the currenty ruleset in memory to disk
service iptables restart : Restarts iptables
Apache Shell Commands
httpd -v : Outputs the build date and version of the Apache server.
httpd -l : Lists compiled in Apache modules
httpd status : Only works if mod_status is enabled and shows a page of active connections
service httpd restart : Restarted Apache web server
MySQL Shell Commands
mysqladmin processlist : Shows active mysql connections and queries
mysqladmin drop databasenamehere : Drops/deletes the selected database
mysqladmin create databasenamehere : Creates a mysql database
Restore MySQL Database Shell Command
mysql -u username -ppassword -h webhost databasename < databasefile.sql : Restores a MySQL database from databasefile.sql
Backup MySQL Database Shell Command
mysqldump -u username -ppassword -h webhost databasename > databasefile.sql : Backup MySQL database to databasefile.sql
kill: terminate a system process
kill -9 PID EG: kill -9 431
kill PID EG: kill 10550
Use top or ps ux to get system PIDs (Process IDs)
Each line represents one process, with a process being loosely defined as a running instance of a program. The column headed PID (process ID) shows the assigned process numbers of the processes. The heading COMMAND shows the location of the executed process.
Putting commands together
Often you will find you need to use different commands on the same line. Here are some examples. Note that the | character is called a pipe, it takes date from one program and pipes it to another.
> means create a new file, overwriting any content already there.
>> means tp append data to a file, creating a newone if it doesn not already exist.
< send input from a file back into a command.
grep User /usr/local/apache/conf/httpd.conf |more
This will dump all lines that match User from the httpd.conf, then print the results to your screen one page at a time.
last -a > /root/lastlogins.tmp
This will print all the current login history to a file called lastlogins.tmp in /root/
tail -10000 /var/log/exim_mainlog |grep domain.com |more
This will grab the last 10,000 lines from /var/log/exim_mainlog, find all occurances of domain.com (the period represents ‘anything’,
— comment it out with a so it will be interpretted literally), then send it to your screen page by page.
netstat -an |grep :80 |wc -l
Show how many active connections there are to apache (httpd runs on port 80)
mysqladmin processlist |wc -l
Show how many current open connections there are to mysql