我的 Fedora 31 中出现了奇怪的行为：
重启后，网络运行正常。几秒钟后，我发现网络速度和延迟各不相同。请查看 iperf 扫描和 ping 分析：
64 bytes from 192.168.0.7: icmp_seq=85 ttl=64 time=0.377 ms
64 bytes from 192.168.0.7: icmp_seq=86 ttl=64 time=0.380 ms
64 bytes from 192.168.0.7: icmp_seq=87 ttl=64 time=0.356 ms
64 bytes from 192.168.0.7: icmp_seq=88 ttl=64 time=0.284 ms
64 bytes from 192.168.0.7: icmp_seq=89 ttl=64 time=0.276 ms
64 bytes from 192.168.0.7: icmp_seq=90 ttl=64 time=0.234 ms
64 bytes from 192.168.0.7: icmp_seq=91 ttl=64 time=0.293 ms
64 bytes from 192.168.0.7: icmp_seq=92 ttl=64 time=4329 ms
64 bytes from 192.168.0.7: icmp_seq=93 ttl=64 time=3304 ms
64 bytes from 192.168.0.7: icmp_seq=94 ttl=64 time=2280 ms
64 bytes from 192.168.0.7: icmp_seq=95 ttl=64 time=1257 ms
64 bytes from 192.168.0.7: icmp_seq=96 ttl=64 time=233 ms
64 bytes from 192.168.0.7: icmp_seq=97 ttl=64 time=2145 ms
64 bytes from 192.168.0.7: icmp_seq=98 ttl=64 time=1098 ms
64 bytes from 192.168.0.7: icmp_seq=99 ttl=64 time=74.5 ms
64 bytes from 192.168.0.7: icmp_seq=100 ttl=64 time=294 ms
64 bytes from 192.168.0.7: icmp_seq=105 ttl=64 time=6029 ms
64 bytes from 192.168.0.7: icmp_seq=106 ttl=64 time=5005 ms
64 bytes from 192.168.0.7: icmp_seq=107 ttl=64 time=3981 ms
64 bytes from 192.168.0.7: icmp_seq=108 ttl=64 time=2956 ms
64 bytes from 192.168.0.7: icmp_seq=109 ttl=64 time=1933 ms
64 bytes from 192.168.0.7: icmp_seq=110 ttl=64 time=909 ms
64 bytes from 192.168.0.7: icmp_seq=111 ttl=64 time=0.362 ms
64 bytes from 192.168.0.7: icmp_seq=112 ttl=64 time=0.295 ms
64 bytes from 192.168.0.7: icmp_seq=113 ttl=64 time=0.297 ms
64 bytes from 192.168.0.7: icmp_seq=114 ttl=64 time=0.300 ms
64 bytes from 192.168.0.7: icmp_seq=115 ttl=64 time=0.316 ms
64 bytes from 192.168.0.7: icmp_seq=116 ttl=64 time=0.381 ms
64 bytes from 192.168.0.7: icmp_seq=117 ttl=64 time=0.376 ms
下面是 iperf：
% iperf -c 192.168.0.7 -e -i 1
------------------------------------------------------------
Client connecting to sun.beach.lan, TCP port 5001 with pid 12703
Write buffer size: 128 KByte
TCP window size: 450 KByte (default)
------------------------------------------------------------
[ 3] local 192.168.0.105 port 42752 connected with 192.168.0.7 port 5001 (ct=0.30 ms)
[ ID] Interval Transfer Bandwidth Write/Err Rtry Cwnd/RTT NetPwr
[ 3] 0.00-1.00 sec 78.7 MBytes 660 Mbits/sec 630/0 0 76K/566 us 145820.76
[ 3] 1.00-2.00 sec 382 KBytes 3.13 Mbits/sec 3/1 1 1K/80125 us 4.88
[ 3] 2.00-3.00 sec 0.00 Bytes 0.00 bits/sec 0/2 0 1K/80125 us 0.00
[ 3] 3.00-4.00 sec 191 KBytes 1.56 Mbits/sec 2/1 0 596K/2243533 us 0.09
[ 3] 4.00-5.00 sec 0.00 Bytes 0.00 bits/sec 0/2 0 596K/2243533 us 0.00
[ 3] 5.00-6.00 sec 0.00 Bytes 0.00 bits/sec 0/2 0 596K/2243533 us 0.00
[ 3] 6.00-7.00 sec 0.00 Bytes 0.00 bits/sec 0/2 0 596K/2243533 us 0.00
[ 3] 7.00-8.00 sec 0.00 Bytes 0.00 bits/sec 0/2 0 596K/2243533 us 0.00
[ 3] 8.00-9.00 sec 0.00 Bytes 0.00 bits/sec 0/2 0 596K/2243533 us 0.00
[ 3] 9.00-10.00 sec 0.00 Bytes 0.00 bits/sec 0/2 0 596K/2243533 us 0.00
[ 3] 0.00-10.25 sec 79.3 MBytes 64.9 Mbits/sec 635/16 1 -1K/1586554 us 5.11
两台机器都通过非托管千兆以太网交换机连接。这是唯一的系统，有问题。
我已经尝试过不同的电缆、不同的介质（电力线、WiFi 上的 LAN）、不同的交换机。但每次我都会遇到一些问题。在最糟糕的情况下，NIC 不再识别插入的电缆。
目前我怀疑是我的网卡。
有人能建议从哪里开始进行故障排除吗？
答案1
如果您将另一台计算机直接插入您的计算机并使用强大的以太网线（例如 cat6）重复不同的测试，会怎样？
看起来是以太网线路出了问题
答案2
其原因尚不清楚。
全新安装解决了该问题。