Sporadically, there are link losses with mvBlueLYNX or network speed is slower than expected


Please check, if the switch supports "autonegotiation" and if it is enabled. If this should not be possible, the mvBlueLYNX" network interface has to be set to the same value. This could be done with mii-tool.

Please start the tool like this:


eth0: negotiated 100baseTx-FD, link ok

mvBL:/home# ./mii-tool --help
usage: ./mii-tool [-VvRrwl] [-A media,... | -F media] [interface ...]
 -V, --version display version information
 -v, --verbose more verbose output
 -R, --reset reset MII to poweron state
 -r, --restart restart autonegotiation
 -w, --watch monitor for link status changes
 -l, --log with -w, write events to syslog
 -A, --advertise=media,... advertise only specified media
 -F, --force=media force specified media technology
media: 100baseT4, 100baseTx-FD, 100baseTx-HD, 10baseT-FD, 10baseT-HD,
 (to advertise both HD and FD) 100baseTx, 10baseT

mvBL:/home# ./mii-tool -v
eth0: negotiated 100baseTx-FD, link ok
 product info: vendor 00:60:6e, model 4 rev 1
 basic mode: autonegotiation enabled
 basic status: autonegotiation complete, link ok
 capabilities: 100baseTx-FD 100baseTx-HD 10baseT-FD 10baseT-HD
 advertising: 100baseTx-FD 100baseTx-HD 10baseT-FD 10baseT-HD
 link partner: 100baseTx-FD 100baseTx-HD 10baseT-FD 10baseT-HD flow-control

  • Capabilities shows the supported modes of mvBlueLYNX" network controller.
  • Advertising shows the adverted modes.
  • Link partner shows the supported modes of the link partner.

E.g. "link partner : 100baseTX-HD" would be a output of a link partner who does not support FD (unusual normally). This could be the case, if an old hub is used, the autonegotiation fails for unknown reasons or the link partner only allows this mode.

Using mii-tool, you can set the link without autonegotiation, for example, 100baseTx-FD.

./mii-tool --force 100baseTx-FD


./mii-tool -w

you can display the link state changes. E.g.:

> eth0: 100 Mbit, full duplex, link ok

Disconnecting the network cable:

> eth0: 100 Mbit, full duplex, no link

Connecting the network cable:

> eth0: 100 Mbit, full duplex, link ok

If you reset to autonegotiation with

> ./mii-tool -r

and afterwards trace the link change with
mii-tool -w
, you will see while disconnecting and connecting the cable, that autonegotiation is done every time.

Link to the IPK: http://beta.matrix-vision.com/mvbl-feed/mii-tool_1.6.0_ppc603e.ipk

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