在我的专用服务器(由OVH托管)上,运行全新安装的Ubuntu 14.04,curl和wget大约需要10秒才能完成一个简单的请求.
$curl -v google.com * Rebuilt URL to: google.com/ * Hostname was NOT found in DNS cache
并且仅在10秒后它才会真正返回一些东西.所以我决定对此进行操作:
write(2,"Hostname was NOT found in DNS ca"...,36) = 36 socket(PF_INET6,SOCK_DGRAM,IPPROTO_IP) = 3 close(3) = 0 mmap(NULL,8392704,PROT_READ|PROT_WRITE,MAP_PRIVATE|MAP_ANONYMOUS|MAP_STACK,-1,0) = 0x7f0a24fb8000 mprotect(0x7f0a24fb8000,4096,PROT_NONE) = 0 clone(child_stack=0x7f0a257b7f70,flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTID,parent_tidptr=0x7f0a257b89d0,tls=0x7f0a257b8700,child_tidptr=0x7f0a257b89d0) = 5047 poll(0,4) = 0 (Timeout) poll(0,8) = 0 (Timeout) poll(0,16) = 0 (Timeout) poll(0,32) = 0 (Timeout) poll(0,64) = 0 (Timeout) poll(0,128) = 0 (Timeout) poll(0,256) = 0 (Timeout) poll(0,1000) = 0 (Timeout) poll(0,1000) = 0 (Timeout) [...] (10 times or so) poll(0,1000) = 0 (Timeout) socket(PF_INET,SOCK_STREAM,IPPROTO_TCP) = 3 write(2,"*",1) = 1 write(2," "," Trying 74.125.228.7...\n",25) = 25
在所有这些超时之后,我可以清楚地看到套接字(PF_INET6)后跟套接字(PF_INET). wget的行为方式相同.
更多相关信息:
$sudo sysctl -p net.ipv6.conf.all.disable_ipv6 = 1 net.ipv6.conf.default.disable_ipv6 = 1 net.ipv6.conf.lo.disable_ipv6 = 1 $sudo cat /etc/default/bind9 RESOLVCONF=yes OPTIONS="-4 -u bind" $cat /proc/sys/net/ipv6/conf/all/disable_ipv6 1
ifconfig没有显示inet6地址.
我怎样才能防止这种情况发生?
您可能需要指出IPv4优先于IPv6,如此链接所述.
https://askubuntu.com/questions/32298/prefer-a-ipv4-dns-lookups-before-aaaaipv6-lookups
原文链接:https://www.f2er.com/ubuntu/348178.html更改/etc/gai.conf下的设置.