Not working properly in containers (Docker)

[elgalu]

Network metrics properly reported in the Host:

|        Network (MBytes/s)       | Disk Util |            Disk MBytes          |             Disk I/O            |
|     Received    |     Sent      |     %     |    MB/s Read    |  MB/s Written |     I/O Read    |   I/O Write   |
|   val  |   avg  |  val  |  avg  | val | avg |  val   |  avg   |  val  |  avg  |   val  |   avg  |  val  |  avg  |
| ------:| ------:| -----:| -----:| ---:| ---:| ------:| ------:| -----:| -----:| ------:| ------:| -----:| -----:|
|  417.2 |  417.2 |   3.0 |   3.0 |   8 |   8 |    0.9 |    0.9 | 370.5 | 370.5 |    220 |    220 | 11897 | 11897 |
|  335.1 |  376.1 |   2.4 |   2.7 |  10 |   9 |    1.4 |    1.1 | 275.5 | 323.0 |    335 |    278 |  9168 | 10532 |
|  434.2 |  395.5 |   3.2 |   2.9 |   9 |   9 |    3.9 |    2.1 | 169.9 | 272.0 |    653 |    403 | 11450 | 10838 |

Network metrics are not visible in the container
Disclaimer: the timeline extracts are not perfectly synchronized

|        Network (MBytes/s)       | Disk Util |            Disk MBytes          |             Disk I/O            |
|     Received    |     Sent      |     %     |    MB/s Read    |  MB/s Written |     I/O Read    |   I/O Write   |
|   val  |   avg  |  val  |  avg  | val | avg |  val   |  avg   |  val  |  avg  |   val  |   avg  |  val  |  avg  |
| ------:| ------:| -----:| -----:| ---:| ---:| ------:| ------:| -----:| -----:| ------:| ------:| -----:| -----:|
|    0.0 |    0.0 |   0.0 |   0.0 |   7 |   9 |    0.9 |    1.3 |  82.4 | 556.4 |    216 |    310 | 20093 |  9335 |
|    0.0 |    0.0 |   0.0 |   0.0 |   9 |   9 |   24.9 |    2.0 | 375.4 | 550.8 |    783 |    325 |  3604 |  9156 |
|    0.0 |    0.0 |   0.0 |   0.0 |  10 |   9 |   60.5 |    3.8 | 103.9 | 537.2 |   1315 |    355 | 12689 |  9263 |

To reproduce

1. generate network I/O outside the container (in the host)
2. start a container without any special flags, without any admin or additional capabilities

TODO

Find a fix with the least possible privileges