Unstable interface on APU1 after changing configuration

[rmaeder]

On my APU1, whenever I make a change to an interface in the web FE, such as changing mtu, MAC, Speed and Duplex, the interface becomes unstable. It drops the link every few seconds and then comes back up, and down, etc.
A reboot fixes the problem, but I wonder whether there is something less drastic that makes the interface behave again.
Here is the output of two consecutive "ifconfig re0" within a few seconds:

re0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
        options=8209b<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,VLAN_HWCSUM,WOL_MAGIC,LINKSTATE>
        ether 00:0d:b9:3f:52:10
        hwaddr 00:0d:b9:3f:52:10
        inet6 fe80::20d:b9ff:fe3f:5210%re0 prefixlen 64 scopeid 0x1 
        nd6 options=21<PERFORMNUD,AUTO_LINKLOCAL>
        media: Ethernet autoselect (none)
        status: no carrier

re0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
        options=8209b<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,VLAN_HWCSUM,WOL_MAGIC,LINKSTATE>
        ether 00:0d:b9:3f:52:10
        hwaddr 00:0d:b9:3f:52:10
        inet6 fe80::20d:b9ff:fe3f:5210%re0 prefixlen 64 scopeid 0x1 
        inet 185.XX.YY.ZZ netmask 0xffffffe0 broadcast 185.XX.YY.ZZZ 
        nd6 options=21<PERFORMNUD,AUTO_LINKLOCAL>
        media: Ethernet autoselect (1000baseT <full-duplex>)
        status: active

The chip is a Realtek RTL8111E. pfSense is 2.4.4_p3
Roman

[stephenw10]

What Coreboot version do you have on that? I'm not aware if anything related that was fixed in an update but if you've never updated it there have been a lot of fixes since release.

Steve

[rmaeder]

@stephenw10
I upgraded the BIOS just days ago (for the first time ever), and it is at v4.9.0.7.
I powered up my backup unit, which still has the original version, 4.0, and did a quick test changing interface properties, and no problems showed up.
That unit is configured for a different ISP, but I will eventually reconfigure it and then I can see whether it also works for the new configuration, with the old BIOS.
Roman

[stephenw10]

Hmm. Well the one I have here seems to work fine and it's running pfSense 2.5 snapshots and Core boot v4.8.0.1.

You might try either of those.

If you have a backup unit though the first thing I would try is load that up with 2.4.4p3 fresh and restore the config into it from the other one. See if the fault follows it. If not re-install the other one and see if the fault remains.

Steve

[rmaeder]

@stephenw10
I reinstalled 2.4.4p3 on my backup unit, loaded the current config, and then connected it to my network in place of the active unit; I did not upgrade the BIOS.
The behaviour is exactly the same. I configured the WAN interface (re0) with an MTU of 1500, which is the same value it has by default. After applying the changes, the interface would lose the link every few seconds, then come back up, until I rebooted. It alternated between

media: Ethernet autoselect (none)

and

media: Ethernet autoselect (1000baseT <full-duplex>)

Roman

[stephenw10]

What is it connected to? Can you put a different switch in between?

I had an old laptop some time ago that had a Realtek NIC and it would not link stably to an SMC switch I had in any OS. Something there was not in compliance with spec but it was not something I could ever resolve.

Steve

[rmaeder]

@stephenw10 said in Unstable interface on APU1 after changing configuration:

What is it connected to? Can you put a different switch in between?

it is connected to a DKT-COMEGA 79741 Fiber gateway. I could connect re2 to another device and see whether it behaves the same way.

[rmaeder]

it is connected to a DKT-COMEGA 79741 Fiber gateway. I could connect re2 to another device and see whether it behaves the same way.

I connected re2 to my laptop; there was no problem changing the interface properties (mtu, autoselect).
The laptop uses the e1000e driver for its Intel NIC. The only difference I could see is in the output of ifconfig: in re0, it is

media: Ethernet autoselect (1000baseT <full-duplex>)

and in re2, it is

media: Ethernet autoselect (1000baseT <full-duplex,master>)

Anyway, I don't think I'll need to touch the interface configuration often enough for this behaviour to be a real problem.

Roman