In most cases you will need root permission to be able to capture packets on an interface. Using tcpdump (with root) to capture the packets and saving them to a file to analyze with Wireshark (using a regular account) is recommended over using Wiresh…

tcpdump command is also called as packet analyzer. tcpdump command will work on most flavors of unix operating system. tcpdump allows us to save the packets that are captured, so that we can use it for future analysis. The saved file can be viewed by…

简介 网络数据包截获分析工具.支持针对网络层.协议.主机.网络或端口的过滤.并提供and.or.not等逻辑语句帮助去除无用的信息. tcpdump - dump traffic on a network 例子 不指定任何参数 监听第一块网卡上经过的数据包.主机上可能有不止一块网卡,所以经常需要指定网卡. tcpdump 监听特定网卡 tcpdump -i en0 监听特定主机 例子:监听本机跟主机182.254.38.55之间往来的通信包. 备注:出.入的包都会被监听. tcpdump hos…

以下将给出9个使用tcpdump的例子,以说明tcpdump的具体使用方法. 1.针对特定网口抓包(-i选项) 当我们不加任何选项执行tcpdump时,tcpdump将抓取通过所有网口的包:使用-i选项,我们可以在某个指定的网口抓包: linux:/tmp/lx # tcpdump -i eth0 tcpdump: verbose output suppressed, use -v or -vv for full protocol decode listening on eth0, link-t…

tcpdump能帮助我们捕捉并保存网络包,保存下来的网络包可用于分析网络负载情况,包可通过tcpdump命令解析,也可以保存成后缀为pcap的文件,使用wireshark等软件进行查看. 以下将给出9个使用tcpdump的例子,以说明tcpdump的具体使用方法. 1.针对特定网口抓包(-i选项) 当我们不加任何选项执行tcpdump时,tcpdump将抓取通过所有网口的包:使用-i选项,我们可以在某个指定的网口抓包: linux:/tmp/lx # tcpdump -i eth0 tcpdum…

转载申明:本文转载自http://www.brendangregg.com/perf.html   请大家看了之后如果要转载一定要注上这个地址!!! ================================================= perf Examples The Linux perf_events T-shirt These are some examples of using the perf Linux profiler, which has also been cal…

By Ravi Saive Under: Linux Commands, Monitoring Tools On: December 26, 2013 http://www.tecmint.com/command-line-tools-to-monitor-linux-performance/ It’s really very tough job for every System or Network administrator to monitor and debugLinux System…

man 手册--nc NCAT(1) Ncat Reference Guide NCAT(1) NAME ncat - Concatenate and redirect sockets SYNOPSIS ncat [OPTIONS...] [hostname] [port] DESCRIPTION Ncat is a feature-packed networking utility which reads and writes data across networks from the com…

目录 nmap使用手册 附录: nmap使用手册 附录: NMAP(1) Nmap Reference Guide NMAP(1) NAME nmap - Network exploration tool and security / port scanner SYNOPSIS nmap [Scan Type...] [Options] {target specification} DESCRIPTION Nmap ("Network Mapper") is an open sourc…

概要 本章对“公平锁”的获取锁机制进行介绍(本文的公平锁指的是互斥锁的公平锁),内容包括:基本概念ReentrantLock数据结构参考代码获取公平锁(基于JDK1.7.0_40)一. tryAcquire()二. addWaiter()三. acquireQueued()四. selfInterrupt()“公平锁”的释放锁的机制在后面一章再做介绍,锁的使用示例请参考“Java多线程系列--“JUC锁”02之 互斥锁ReentrantLock”. 转载请注明出处:http://www.cnbl…