摘要：
invocation operation1. 添加到队列前，无依赖：readynot executingnot finishednot cancellednot concurrent2. 添加到队列前，有依赖：not readynot executingnot finishednot cancellednot concurrent3. 添加到队列，并且有一个依赖，在依赖执行完以前：not readynot executingnot finishednot cancellednot concurrent4. 添加到队列，并且有一个依赖，在依赖执行完以前，取消掉：readynot executin 阅读全文
摘要：
1.Frist, make sure you have ppp installedyum install -y ppp iptablesyum install perl2.Download lastest version pptpd rpm packagewget http://acelnmp.googlecode.com/files/pptpd-1.3.4-1.rhel5.1.x86_64.rpm3.Installing the rpmrpm -ivh pptpd-1.3.4-1.rhel5.1.i386.rpm4.Open the file /etc/ppp/options.pptpdvi 阅读全文