Linux - NetworkingThis forum is for any issue related to networks or networking.
Routing, network cards, OSI, etc. Anything is fair game.
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I have a motherboard with two Ethernet ports, and I would like to get a connection on both ports.
Eth0 already has a connection and can be used without problems. Eth1 however shows up as "unavailable" in nmcli. How can I make this Ethernet port usable as well?
Some related information:
Code:
ethtool eth1
Supported ports: [ TP MII ]
Supported link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
Supported pause frame use: No
Supports auto-negotiation: Yes
Advertised link modes: 100baseT/Half 100baseT/Full
Advertised pause frame use: Symmetric Receive-only
Advertised auto-negotiation: Yes
Link partner advertised link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
Link partner advertised pause frame us Symmetric
Link partner advertised auto-negotiation: Yes
Speed: 100Mb/s
Duplex: Full
Port: MII
PHYAD: 1
Transceiver: internal
Auto-negotiation: on
Supports Wake-on: pumbag
Wake-on: d
Current message level: 0x00000007 (7)
drv probe link
Link detected: yes
Code:
ifconfig eth1
eth1 Link encap:Ethernet HWaddr F6:7B:7B:7B:E9:C2
UP BROADCAST MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:0 (0.0 B) TX bytes:0 (0.0 B)
Code:
ip addr
eth1: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast qlen 1000
link/ether f6:7b:7b:7b:e9:c2 brd ff:ff:ff:ff:ff:ff
I have a motherboard with two Ethernet ports, and I would like to get a connection on both ports.
Eth0 already has a connection and can be used without problems. Eth1 however shows up as "unavailable" in nmcli. How can I make this Ethernet port usable as well?
What's the precise nmcli output?
How is the interface configured (in Red Hat and derivatives, /etc/sysconfig/network-scripts, in Ubuntu, from memory, /etc/network/interfaces)?
Perhaps this part of the nmcli man page helps:
Code:
nmcli dev disconnect iface em2
disconnects a connection on interface em2 and marks the device
as unavailable for auto‐connecting. That's why no connection
will automatically be activated on the device until the device's
"autoconnect" is set to TRUE or user manually activates a
connection.
In other words, you need to do something to connect the interface manually or automatically.
My settings are set to autoconnect, so I don't think that is the problem here.
Code:
nmcli dev
DEVICE TYPE STATE CONNECTION
eth0 ethernet connected eth0
eth1 ethernet unavailable --
lo loopback unmanaged --
sit0 sit unmanaged --
Code:
nmcli con
NAME UUID TYPE DEVICE
eth0 xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx 802-3-ethernet eth0
eth1 xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx 802-3-ethernet --
Code:
nmcli -p con show eth1
===============================================================================
Connection profile details (eth1)
===============================================================================
connection.id: eth1
connection.uuid: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
connection.interface-name: eth1
connection.type: 802-3-ethernet
connection.autoconnect: yes
connection.autoconnect-priority: 0
connection.timestamp: 0
connection.read-only: no
connection.permissions:
connection.zone: --
connection.master: -
connection.slave-type: --
connection.secondaries:
connection.gateway-ping-timeout: 0
-------------------------------------------------------------------------------
802-3-ethernet.port: --
802-3-ethernet.speed: 0
802-3-ethernet.duplex: --
802-3-ethernet.auto-negotiate: yes
802-3-ethernet.mac-address: --
802-3-ethernet.cloned-mac-address: --
802-3-ethernet.mac-address-blacklist:
802-3-ethernet.mtu: auto
802-3-ethernet.s390-subchannels:
802-3-ethernet.s390-nettype: --
802-3-ethernet.s390-options:
-------------------------------------------------------------------------------
ipv4.method: auto
ipv4.dns:
ipv4.dns-search:
ipv4.addresses:
ipv4.gateway: --
ipv4.routes:
ipv4.route-metric: -1
ipv4.ignore-auto-routes: no
ipv4.ignore-auto-dns: no
ipv4.dhcp-client-id: --
ipv4.dhcp-send-hostname: yes
ipv4.dhcp-hostname: --
ipv4.never-default: no
ipv4.may-fail: yes
-------------------------------------------------------------------------------
ipv6.method: auto
ipv6.dns:
ipv6.dns-search:
ipv6.addresses:
ipv6.gateway: --
ipv6.routes:
ipv6.route-metric: -1
ipv6.ignore-auto-routes: no
ipv6.ignore-auto-dns: no
ipv6.never-default: no
ipv6.may-fail: yes
ipv6.ip6-privacy: -1 (unknown)
ipv6.dhcp-send-hostname: yes
ipv6.dhcp-hostname: --
-------------------------------------------------------------------------------
I can confirm that the cable is attached, and I have tried with other cables I know works fine.
I have tried connecting only eth1 as well, and there is no reaction to it. I still can't get no connection.
You must also check your rp_filter settings. If rp_filter validates packets, you will struggle till blue in the face to try and get dual nics properly working.
Here is a quick explanation of reverse path filter.
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