通常情况下,linux系统网络连通性的检测有两种方法:
1、通过“ping指令 + 目标IP” 或者 “ping指令 + 目标IP域名”
注意针对IPv6地址的IP网络检测需要试用ping6,同时ping6中不能使用参数hops,因为IP6源码中已经舍弃了路由,见如下英文解释:
SYNOPSIS
ping [-aAbBdDfhLnOqrRUvV] [-c count] [-F flowlabel] [-i interval] [-I interface] [-l preload] [-m mark] [-M pmtudisc_option] [-N nodeinfo_option]
[-w deadline] [-W timeout] [-p pattern] [-Q tos] [-s packetsize] [-S sndbuf] [-t ttl] [-T timestamp option] [hop ...] destinationt.
Notes:
ping6 is IPv6 version of ping, and can also send Node Information Queries (RFC4620). Intermediate hops may not be allowed, because IPv6 source
routing was deprecated.
ping指令调用时的常用参数:
# Parameter:
# -c the number of packages to send
# -i internel between two packages
# -W timeout seconds
# Check the connect status of internet function check_ip_status() { ping -c 3 -i 0.2 -W 3 $1 &> /dev/null if [ $? -eq 0 ];then return 0 else return -1 fi }
check_ip_status 10.74.120.104
if [ $? -ne 0 ];then echo "cannot connect guestconf server:10.74.120.104" exit -1 fi
2、使用“curl指令 + IP域名”
#!/usr/bin/bash # #检测网络链接&&ftp上传数据 function networkAndFtp() { #超时时间 timeout=5 #目标域名 target=www.baidu.com #获取响应状态码 ret_code=`curl -I -s --connect-timeout $timeout $target -w %{http_code} | tail -n1` if [ "x$ret_code" = "x200" ]; then #网络畅通 else #网络不畅通 fi }
在调用shell函数时需要注意一下两个地方:
1、函数的返回值应采用echo
2、函数的状态码应采用return