I have a zync card running linux, with two ethernets ports with a dual PHY and only one MDIO controller.

When I run ifconfig I can see both eth0 and eth1 and netstat -rn shows the two entries for eth0 and one for eth1.

However I am witnessing connection issues, there is something not quite right with the hookup of the dual MACs.

eth1 does not seem to come up properly; get a ip: RTNETLINK answers: File exists error. Board can crash when trying to reboot.

More specifically, ifdown hangs. For example:

run-parts /etc/network/if-down.d
ip addr flush dev eth0
ip link set eth0 down
xemacps e000c000.ps7-ethernet: link down
run-parts /etc/network/if-post-down.d

Any advice on how to handle this issue would be very much appreciated.

I would also like to add that when creating SSH connection using, eg, Putty and Filezilla, the connection seems to be made ok but then often dies unexpectedly after a minute or so.

Copy your interface configuration,
1. cat /etc/sysconfig/network-scripts/ifcfg-eth0
2. cat /etc/sysconfig/network-scripts/ifcfg-eth1

And copy the following,
1. ip a
2. netstat -rn
3. dmesg | grep eth0 and eth1

# cat /etc/network/interfaces
# Configure Loopback
auto lo
iface lo inet loopback

# Configure Ethernet interface 0
# allow-hotplug eth0
auto eth0
iface eth0 inet static
address 192.168.1.3
gateway 192.168.1.1
netmask 255.255.255.0

# Configure Ethernet interface 1
# allow-hotplug eth1
auto eth
iface eth1 inet static
address 192.168.3.210
gateway 192.168.3.1
netmask 255.255.255.0
# dns-nameservers 192.168.3.141 192.168.3.143

# iface eth1 inet dhcp


ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast qlen 1000
link/ether 00:0a:35:00:01:22 brd ff:ff:ff:ff:ff:ff
inet 192.168.1.3/24 scope global eth0
valid_lft forever preferred_lft forever
inet6 fe80::20a:35ff:fe00:122/64 scope link
valid_lft forever preferred_lft forever
3: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast qlen 1000
link/ether 00:0a:35:00:01:23 brd ff:ff:ff:ff:ff:ff
inet 192.168.3.210/24 scope global eth1
valid_lft forever preferred_lft forever
inet6 fe80::20a:35ff:fe00:123/64 scope link
valid_lft forever preferred_lft forever
4: tunl0: <NOARP> mtu 0 qdisc noop
link/ipip 0.0.0.0 brd 0.0.0.0
5: sit0: <NOARP> mtu 1480 qdisc noop
link/sit 0.0.0.0 brd 0.0.0.0

netstat -rn
Kernel IP routing table
Destination Gateway Genmask Flags MSS Window irtt Iface
0.0.0.0 192.168.1.1 0.0.0.0 UG 0 0 0 eth0
192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
192.168.3.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1

# dmesg | grep eth0 and eth1
grep: and: No such file or directory
grep: eth1: No such file or directory


I do not have separate files for eth0 and eth1. Are these supposed to be automatically generated or am I supposed to generate them as part of the installation process.

Please note this is not a standard linux distribution but a xilinx special.

Having been trawling through xilinx forums all day I found a couple of things to try. After modifying the device tree so that both eth0 and eth1 reference the mdio, rather than just eth0 and eth1 just having the phy handle phy1. Now when we start up there is a similar directory structure for both eth0 and eth1 rathre than the statistics etc just comming under eth0.

Also modified the driver xilinx_emacps.c function static void xemacps_adjust_link(struct net_device *ndev) adding the lines
if (lp->enetnum == 1)
xemacps_mdio_read(lp->mii_bus, lp->phy_dev->addr, 0);


to the end of the function.
eth0 is now working fine and ifdown and ifup work without crashing.

However we are still seeing the RTNETLINK answers: File exists error at reboot and also when ever we check the operational status of eth1 it it always down even after running ifup eth1, which nolonger errors.

Also can nolonger putty into the devide using the ip address for eth0.

Any further suggestions for how I can get the second ethernet port up and running greatfully received.

first do this action. you get good result....

I know nothing of your distro, so feel free to ignore me. However, I see a typo (based on typical Unix/Linux conventions:

~~~
# Configure Ethernet interface 0
# allow-hotplug eth0
auto eth0 <-- Says 'auto ethx'
iface eth0 inet static

...

# Configure Ethernet interface 1
# allow-hotplug eth1
auto eth <-- Says 'auto eth' (no 'x')
iface eth1 inet static
~~~

Seems as if the lack of a numerical designation might cause issues if you are going to expect it to be called "eth1", and you don't declare it at the beginning of the config.

Thanks for the advice I re-checked the /etc/network/interfaces file and it is now correct:

# cat /etc/network/interfaces
# Configure Loopback
auto lo
iface lo inet loopback

# Configure Ethernet interface 0
# allow-hotplug eth0
auto eth0
iface eth0 inet static
address 192.168.1.3
gateway 192.168.1.1
netmask 255.255.255.0

# Configure Ethernet interface 1
# allow-hotplug eth1
auto eth1
iface eth1 inet static
address 192.168.3.210
# gateway 192.168.3.1
netmask 255.255.255.0
# dns-nameservers 192.168.3.141 192.168.3.143

# iface eth1 inet dhcp

RTNETLINK answers: File exists error also cured by using the same gateway fot eth0 and eth1.

Both ethernet connection now appear to be up and working ok.

So it was just a typo? Happy to hear!