I am trying to connect two workstations (CentOS 3&4) directly using a
straight through cat 5e cable with a crossover adapter on one of the
ends. Both hosts have gigabit-capable ethernet card. According to
lspci host 1 has:
03:0e.0 Ethernet controller: Intel Corporation 82545EM Gigabit
Ethernet Controller (Copper) (rev 01)
and host 2 has:
05:00.0 Ethernet controller: Marvell Technology Group Ltd. 88E8050
Gigabit Ethernet Controller (rev 17)
In order to get this controller work on host 2, I had to download and
install a more recent version of the sk98lin driver. Host 2 runs
CentOS 4. Host 1 runs CentOS 3 (with a stock e1000 driver).
After I setup networking, ethtool reported for both hosts that the
link runs at 100Mbps even though it says in both cases that the
capability for
1000baseT/Half 1000baseT/Full modes and exists and is being
advertised. If I force 1000Mbps speed with "ethtool -s eth1 speed
1000", I get:
# ethtool eth1
Settings for eth1:
Supported ports: [ TP ]
Supported link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Half 1000baseT/Full
Supports auto-negotiation: Yes
Advertised link modes: 1000baseT/Half 1000baseT/Full
Advertised auto-negotiation: No
Speed: Unknown! (65535)
Duplex: Unknown! (255)
Port: Twisted Pair
PHYAD: 0
Transceiver: internal
Auto-negotiation: on
Supports Wake-on: g
Wake-on: g
and the eth1 link stops working. What could be a problem here? I tried
loading both drivers with the parameter for 1000Mbps speed parameters
but that didn't help.
( I used on host 1, alias eth1 e1000 Speed=1000
host 2, alias eth1 sk98lin Speed_A=1000 Speed_B=1000)
-akop
* on the Wed, Jan 25, 2006 at 05:40:41PM -0800, Akop Pogosian was tippering:> I am trying to connect two workstations (CentOS 3&4) directly using a > straight through cat 5e cable with a crossover adapter on one of the > ends. Both hosts have gigabit-capable ethernet card. According to > lspci host 1 has:IIRC, one does not need a crossover cable to connect between two gigabit capable hosts. You can give it a shot. -- Bruno Delbono Open-Systems Group Inc. http://www.open-systems.org/users/bruno/ -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: application/pgp-signature Size: 189 bytes Desc: not available URL: <http://lists.centos.org/pipermail/centos/attachments/20060125/a1f6c8e1/attachment-0005.sig>
Bruno S. Delbono wrote:> * on the Wed, Jan 25, 2006 at 05:40:41PM -0800, Akop Pogosian was tippering: > >> I am trying to connect two workstations (CentOS 3&4) directly using a >> straight through cat 5e cable with a crossover adapter on one of the >> ends. Both hosts have gigabit-capable ethernet card. According to >> lspci host 1 has: >> > > IIRC, one does not need a crossover cable to connect between two gigabit > capable hosts. > > You can give it a shot. >Perhaps I'm just dense, but how would two ethernet cards talk to eachother over a straight ethernet cable? I don't profess to be an expert in gigabit ethernet protocols, but I believe it HAS to be a crossover cable if you want to directly connect two hosts. If that's not the case, someone please correct me. Best regards,
} I am trying to connect two workstations (CentOS 3&4) directly using a } straight through cat 5e cable with a crossover adapter on one of the } ends. Both hosts have gigabit-capable ethernet card. According to } lspci host 1 has: remove the crossover adapter and try again - rh -- Robert Hanson - Abba Communications Computer & Internet Services (509) 624-7159 - www.abbacomm.net
Akop Pogosian wrote:> I am trying to connect two workstations (CentOS 3&4) directly using a > straight through cat 5e cable with a crossover adapter on one of the > ends. Both hosts have gigabit-capable ethernet card. According to > lspci host 1 has: > > 03:0e.0 Ethernet controller: Intel Corporation 82545EM Gigabit > Ethernet Controller (Copper) (rev 01) > > and host 2 has: > > 05:00.0 Ethernet controller: Marvell Technology Group Ltd. 88E8050 > Gigabit Ethernet Controller (rev 17) > > In order to get this controller work on host 2, I had to download and > install a more recent version of the sk98lin driver. Host 2 runs > CentOS 4. Host 1 runs CentOS 3 (with a stock e1000 driver). > > After I setup networking, ethtool reported for both hosts that the > link runs at 100Mbps even though it says in both cases that the > capability for > 1000baseT/Half 1000baseT/Full modes and exists and is being > advertised. If I force 1000Mbps speed with "ethtool -s eth1 speed > 1000", I get: > > # ethtool eth1 > Settings for eth1: > Supported ports: [ TP ] > Supported link modes: 10baseT/Half 10baseT/Full > 100baseT/Half 100baseT/Full > 1000baseT/Half 1000baseT/Full > Supports auto-negotiation: Yes > Advertised link modes: 1000baseT/Half 1000baseT/Full > Advertised auto-negotiation: No > Speed: Unknown! (65535) > Duplex: Unknown! (255) > Port: Twisted Pair > PHYAD: 0 > Transceiver: internal > Auto-negotiation: on > Supports Wake-on: g > Wake-on: g > > and the eth1 link stops working. What could be a problem here? I tried > loading both drivers with the parameter for 1000Mbps speed parameters > but that didn't help. > > ( I used on host 1, alias eth1 e1000 Speed=1000 > host 2, alias eth1 sk98lin Speed_A=1000 Speed_B=1000) >Are you using a 1000 Mbps compatible crossover adapter? For 1000 Mbps to function, it needs two pairs to be crossed-over -- see http://www.cabling-design.com/references/pinouts/1000base_t_crossover.shtml for the proper pin layout. HTH.
Apparently the network connection between these two hosts works with or without the cross-over adapter (which crosses two pairs of wires) at 100Mbps. Forcing 1000Mbps with ethtool does not work. However, the host with the Marvell Technology group ethernet adapter also has an Intel EtherExpress 1000 adapter. So, I tried connecting the cable to it and it worked instantly. There is probably some interoperability issue between Intel EE1000 and the Marvell adapter hardware and/or software. -akop