之前服务器 ping 有 dup 问题，一直没解决，不过想想这么拖着也不是个事，今天看了半天也没什么头绪，所以来 V2 问问大家有什么思路。
表现如下：
wordpress 则表现正常，使用 WireShark 抓包时并没有发现 https 连接有这个现象。
 |
1
LPeJuN6lLsS9 Nov 19, 2017
我的也是，openvz 的 vps。dup 的 ttl 也是 128。venet0:0 的广播地址和 ip 地址一样，很可疑但不懂
tcpdump 看了下，全部是在环回里发生的，tcp 也没问题，就不管了 |
 |
2
sublimevsatom Nov 19, 2017
|
 |
3
RalphHuang Nov 19, 2017
Windows Server，做过 NLB 的，ping NLB 的虚 IP 也会出现这个现象，ping 各自的网卡 IP 就不会有这个现象，不明白是为啥
|
 |
4
sjx95 OP @sublimevsatom 嗯，我知道 dup 是什么意思，可是会是什么原因造成的呢？
|
|
6
sublimevsatom Nov 20, 2017
这里有说了一些原因，仔细看。
The ping utility will report duplicate and damaged packets. Duplicate packets should never occur when pinging a unicast address, and seem to be caused by inappropriate link-level retransmissions. Duplicates may occur in many situations and are rarely (if ever) a good sign, although the presence of low levels of duplicates may not always be cause for alarm. Duplicates are expected when pinging a broadcast or multicast address, since they are not really duplicates but replies from different hosts to the same request. Damaged packets are obviously serious cause for alarm and often indicate broken hardware somewhere in the ping packet ’ s path (in the network or in the hosts). |
|
7
sjx95 OP @sublimevsatom 别说的好像我瞎一样好吧…
我这种情况，本机 ping 到本机，跟链路层大概没多少关系吧？就算是有关系，那怎么解释 ICMPv6 工作正常不会 dup ？ |
Select Language