How to block an IP using iptables? iptables -A INPUT -s xx.xx.xx.xx -j DROP How to block an IP for a specific port: iptables -A INPUT -p tcp -s xx.xx.xx.xx –dport PORT -j DROP How to allow access to an IP? Grew, up and. Issues viagra On hold cracks of. […]
Tag: number
Quick check for a ddos via number of connections
A quick and usefull command for checking if a server is under ddos is: netstat -anp |grep ‘tcp\|udp’ | awk ‘{print $5}’ | cut -d: -f1 | sort | uniq -c | sort -n That will list the IPs taking the most amount of connections to a server. It is […]
System monitoring with Conky
My number one favorite system monitor used to be Gkrellm, a small GUI tool that displays system information such as CPU usage, memory and hard drive usage, network throughput, and so forth. Recently, I discovered Conky, which is another system monitoring tool that works extremely well. One of the nice […]
When To Use Indexes In MySQL
This comes up in discussions almost every new project I work on, because it’s a very important thing to consider when designing a database. When deciding when and how to create an index in your MySQL database, it’s important to consider how the data is being used. Let’s say you […]
Apache Optimization
MaxClients ————— The number of worker processes is limited by the parameter MaxClients. MaxClients = Total RAM dedicated to the web server / Max child process size. The default value of MaxClients is 150. If we have a server with 1gb of ram and child process take an average size […]
Howto: Check Apache Connections
How to check number of connections to the Apache server? netstat command will show you the accurate connections to each of your service. In order to check the number of connections to port 80, use the netstat command and grep the Apache port. List the connections to port 80: netstat […]
Using tmpfs for MySQL tmpdir setting
This is incredible, by the way. Any time MySQL needs to use a tmp table on disk, you can make it use RAM disk instead. WARNING: if the tmpfs partition you make isn’t big enough, MySQL will not be able to complete queries. Make sure you have enough RAM to […]