Linux Mint에서 이더넷에 연결할 수 없습니다

약 2주 전에 Mint 20.1 서버에 바이러스 백신 소프트웨어(ESET nod32)를 설치했습니다. 그러나 Linux에 전혀 최적화되지 않았다는 사실을 발견한 후(기본적으로 모든 포트와 연결을 차단하고 방화벽 관리자를 제공하지 않음) 이를 제거하고 연결이 다시 작동하기 시작했습니다. 최근 Squid 프록시 서버를 설정하려고 시도한 후 이더넷 연결이 다시 작동하지 않았습니다. 일부 진단에서는 서버가 연결을 감지하고 있고 드라이버가 제대로 작동하며 이 라우터에 연결된 다른 장치에는 문제가 없는 것으로 나타나므로 이것이 구성 문제인 것으로 의심됩니다. 현재 USB Wi-Fi 어댑터를 통해 임시 연결을 얻을 수 있다는 점도 주목할 가치가 있습니다.

이것은 내 inxi -Fxz의 출력입니다.

System:
  Kernel: 5.4.0-66-generic x86_64 bits: 64 compiler: gcc v: 9.3.0 
  Desktop: Cinnamon 4.8.6 Distro: Linux Mint 20.1 Ulyssa 
  base: Ubuntu 20.04 focal 
Machine:
  Type: Server System: Dell product: PowerEdge T320 v: N/A serial: <filter> 
  Mobo: Dell model: 0W7H8C v: A03 serial: <filter> BIOS: Dell v: 1.5.1 
  date: 03/08/2013 
Battery:
  Device-1: hidpp_battery_1 model: Logitech Wireless Mouse Dell WM514 
  charge: 55% (should be ignored) status: Discharging 
CPU:
  Topology: Quad Core model: Intel Xeon E5-2407 0 bits: 64 type: MCP 
  arch: Sandy Bridge rev: 7 L2 cache: 10.0 MiB 
  flags: avx lm nx pae sse sse2 sse3 sse4_1 sse4_2 ssse3 vmx bogomips: 17600 
  Speed: 1200 MHz min/max: 1200/2200 MHz Core speeds (MHz): 1: 1200 2: 1200 
  3: 1200 4: 1200 
Graphics:
  Device-1: Matrox Systems G200eR2 vendor: Dell driver: mgag200 v: kernel 
  bus ID: 06:00.0 
  Display: x11 server: X.Org 1.20.9 driver: modesetting unloaded: fbdev,vesa 
  resolution: 1600x900~60Hz 
  OpenGL: renderer: llvmpipe (LLVM 11.0.0 256 bits) v: 4.5 Mesa 20.2.6 
  direct render: Yes 
Audio:
  Message: No Device data found. 
Network:
  Device-1: Broadcom and subsidiaries NetXtreme BCM5720 2-port Gigabit 
  Ethernet PCIe 
  vendor: Dell driver: tg3 v: 3.137 port: ecc0 bus ID: 01:00.0 
  IF: eno1 state: up speed: 100 Mbps duplex: full mac: <filter> 
  Device-2: Broadcom and subsidiaries NetXtreme BCM5720 2-port Gigabit 
  Ethernet PCIe 
  vendor: Dell driver: tg3 v: 3.137 port: ecc0 bus ID: 01:00.1 
  IF: eno2 state: down mac: <filter> 
  Device-3: NetGear type: USB driver: mt76x2u bus ID: 1-1.2:6 
  IF: wlx3894edc5d6e1 state: up mac: <filter> 
Drives:
  Local Storage: total: 1.46 TiB used: 12.68 GiB (0.9%) 
  ID-1: /dev/sda vendor: Dell PowerEdge RAID Card model: PERC H710 
  size: 278.88 GiB 
  ID-2: /dev/sdb vendor: Dell PowerEdge RAID Card model: PERC H710 
  size: 278.88 GiB 
  ID-3: /dev/sdc vendor: Dell PowerEdge RAID Card model: PERC H710 
  size: 931.00 GiB 
  ID-4: /dev/sdd type: USB vendor: Dell model: Internal Dual SD 
  size: 1.90 GiB 
RAID:
  Hardware-1: Broadcom / LSI MegaRAID SAS 2208 [Thunderbolt] 
  driver: megaraid_sas v: 07.713.01.00-rc1 bus ID: 08:00.0 
Partition:
  ID-1: / size: 273.00 GiB used: 12.68 GiB (4.6%) fs: ext4 dev: /dev/sda5 
Sensors:
  System Temperatures: cpu: 31.0 C mobo: N/A 
  Fan Speeds (RPM): N/A 
Info:
  Processes: 229 Uptime: 1h 24m Memory: 15.59 GiB used: 1.46 GiB (9.4%) 
  Init: systemd runlevel: 5 Compilers: gcc: 9.3.0 Shell: bash v: 5.0.17 
  inxi: 3.0.38

ethtool eno1의 출력은 다음과 같습니다.

Settings for eno1:
    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
    Supported FEC modes: Not reported
    Advertised link modes:  10baseT/Half 10baseT/Full 
                            100baseT/Half 100baseT/Full 
                            1000baseT/Half 1000baseT/Full 
    Advertised pause frame use: Symmetric
    Advertised auto-negotiation: Yes
    Advertised FEC modes: Not reported
    Link partner advertised link modes:  10baseT/Half 10baseT/Full 
                                         100baseT/Half 100baseT/Full 
    Link partner advertised pause frame use: Symmetric
    Link partner advertised auto-negotiation: Yes
    Link partner advertised FEC modes: Not reported
    Speed: 100Mb/s
    Duplex: Full
    Port: Twisted Pair
    PHYAD: 1
    Transceiver: internal
    Auto-negotiation: on
    MDI-X: on
    Supports Wake-on: g
    Wake-on: d
    Current message level: 0x000000ff (255)
                   drv probe link timer ifdown ifup rx_err tx_err
    Link detected: yes

어떤 아이디어가 있나요?