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大量“MAC CTRL”数据包-网口有缺陷？

tag-icon • tag-icon networking centos ethernet wireshark
大量“MAC CTRL”数据包-网口有缺陷？

我的服务器的一个网络端口出现了异常行为。它似乎无法处理/响应任何流量（ping 等）。以下是使用“ifconfig”（分配的静态地址为 10.100.0.80）列出的内容

eth0      Link encap:Ethernet  HWaddr 00:18:7D:0E:53:8B
          inet addr:10.100.0.80  Bcast:10.255.255.255  Mask:255.0.0.0
          inet6 addr: fe80::218:7dff:fe0e:538b/64 Scope:Link
          UP BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:802 errors:0 dropped:799 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:57099 (55.7 KiB)  TX bytes:2410880 (2.2 MiB)
          Interrupt:16

存在大量“TX 字节”。如果此端口直接连接到另一台机器，TX 字节将继续快速增加，Wireshark 会获取以下内容。

Wireshark 捕获

唯一没有乱七八糟的数据包是偶尔从我的笔记本电脑发出的数据包（如数据包 28）。我不确定这些 MAC CTRL 数据包是什么，或者这是否是其他东西的副作用。

以下是 K12 文本格式的捕获。

+---------+---------------+----------+
14:59:22,793,169   ETHER
|0   |01|80|c2|00|00|01|00|18|7d|0e|53|8b|88|08|00|01|1f|ff|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|

+---------+---------------+----------+
14:59:22,797,366   ETHER
|0   |01|80|c2|00|00|01|00|18|7d|0e|53|8b|88|08|00|01|1f|ff|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|

+---------+---------------+----------+
14:59:22,801,559   ETHER
|0   |01|80|c2|00|00|01|00|18|7d|0e|53|8b|88|08|00|01|1f|ff|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|

无论端口设置为获取 DHCP 地址（尽管位于 DHCP 服务的网络上，但无法获取）还是静态地址，似乎都会发生这种情况。

它在安装 CentOS 6.6 OS（以单用户模式启动并正常启动）和使用 CentOS 6.8 启动到实时 CD/USB 时都会发生这种情况，因此不确定这是否是 CentOS 6.X 特有的问题，尽管到目前为止还没有发生过这种情况。同一台服务器有第二个以太网 (eth1) 端口，似乎运行正常。

ETA ethtool 输出与 grawity 建议的一致，eth0 是故障端口

ethtool eth0
Settings for eth0:
        Supported ports: [ TP ]
        Supported link modes:   10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
                                1000baseT/Half 1000baseT/Full
        Supported pause frame use: No
        Supports auto-negotiation: Yes
        Advertised link modes:  10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
                                1000baseT/Half 1000baseT/Full
        Advertised pause frame use: Symmetric
        Advertised auto-negotiation: Yes
        Link partner advertised link modes:  10baseT/Half 10baseT/Full
                                             100baseT/Half 100baseT/Full
                                             1000baseT/Half 1000baseT/Full
        Link partner advertised pause frame use: Symmetric
        Link partner advertised auto-negotiation: Yes
        Speed: 1000Mb/s
        Duplex: Full
        Port: Twisted Pair
        PHYAD: 1
        Transceiver: internal
        Auto-negotiation: on
        MDI-X: off
        Supports Wake-on: g
        Wake-on: g
        Current message level: 0x000000ff (255)
                               drv probe link timer ifdown ifup rx_err tx_err
        Link detected: yes

ethtool eth1
Settings for eth1:
        Supported ports: [ TP ]
        Supported link modes:   10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
                                1000baseT/Half 1000baseT/Full
        Supported pause frame use: No
        Supports auto-negotiation: Yes
        Advertised link modes:  10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
                                1000baseT/Half 1000baseT/Full
        Advertised pause frame use: Symmetric
        Advertised auto-negotiation: Yes
        Link partner advertised link modes:  10baseT/Half 10baseT/Full
                                             100baseT/Half 100baseT/Full
                                             1000baseT/Full
        Link partner advertised pause frame use: No
        Link partner advertised auto-negotiation: Yes
        Speed: 1000Mb/s
        Duplex: Full
        Port: Twisted Pair
        PHYAD: 1
        Transceiver: internal
        Auto-negotiation: on
        MDI-X: off
        Supports Wake-on: g
        Wake-on: g
        Current message level: 0x000000ff (255)
                               drv probe link timer ifdown ifup rx_err tx_err
        Link detected: yes

没发现什么不对劲的地方？我会用 ethtool 查看暂停帧。

答案1

“暂停”帧有时用于以太网级流量控制。

您可以看到它们的使用情况以及速度正在协商中ethtool。这里奇怪的是，eth0 声称不支持暂停帧，但提供它们的用途反正：

Settings for eth0:
        Supported pause frame use: No                       <- what eth0 supports
        Advertised pause frame use: Symmetric               <- what eth0 offers
        Link partner advertised pause frame use: Symmetric  <- what your switch offers

当然，除非网卡正在接收大量数据，否则它不应该发送暂停帧——显然，如果它说不支持暂停帧，那它就不应该发送它们根本...

尝试使用以下方法禁用它ethtool -A eth0 rx off tx off（这可能是驱动程序错误，也可能是硬件问题；我不知道。）或者，禁用流量控制在开关上该特定端口。

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