Questions tagged [ethernet]

Ethernet is the most common set of standards for wired connections in local area networks.

Ethernet is the most common set of standards for wired connections in local area networks.

Originally designed in the 1970s, Ethernet had a data rate of 10 megabits per second. Later, Ethernet was extended to support rates of 100 megabits/second, 1 gigabit/second, 10 gigabits/second and 100 gigabits/second.

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Why 10GbE card cannot negotiate 10Gbit with Windows 2012R2?

The Problem I've got four identical blade servers. I've got Windows Server 2012 R2 on one blade and Xen on all the others. On the Windows-hosted server (only) the 10GbE NICs cannot negotiate 10Gbit. They settle at 1Gbit only. 10GbE on Xen hosts…
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TIA 568A vs. B Wiring for Long Ethernet Run

I have a long Ethernet run (about 280 ft/85 m) that goes through a conduit between two buildings. On each end, I have an APC Ethernet surge protector that is grounded to the main ground for each building. While I had some trouble getting it to work…
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How do fiber Ethernet transmitters set their power output?

I've noticed that fiber-optic SFP modules from Cisco and the like often specify a range of power outputs, such as -3 to -9 dBm. What determines the actual power output we should expect to see from such modules? Is it determined dynamically, or…
John Zwinck
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Supress FreeBSD "link down: cable prοblem?" messages

I have a FreeBSD lab machine that is regularly connected and disconnected from the network, sometimes to borrow the port temporarily for another machine and other times to test the ability of certain software to recover from losing the network…
Moshe Katz
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Sanity Check: Is my CAT5e cable probably bad, or do I just need different connectors?

I'm working with a small company, and since I'm the only one with even a half-ounce of network infrastructure experience I've got the job of wiring up our network. So please forgive my newbie-ness. Needed to run some CAT5e cable up the outside wall…
DanM
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Is is possible to put a tagged vlan on one physical interface on a Force10 S50N switch?

I servers that have a shared ethernet port for IPMI and the first NIC. They have 4-1GbE nics. I would like to bond the nics via LACP while still being able to access the IPMI over a tagged vlan only on the first physical port since the IPMI is only…
Wren T.
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How to change 'Advertised pause frame use' and autonegotiation setting on gigabit NIC

I'm investigating some poor nfs performance on a new server, as compared to an old server. Both the old and the new server are nfs clients, and they connect to the same exact NetApp nfs server. My specific question: How to I change the…
Banjer
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Can our firewall detect traffic sniffing inside the network?

We use Cisco ASA's firewall and NAT functions in our network (200 computers). Is there any possibility to configure Cisco ASA to detect traffic sniffering (for example wireshark) and network inspection(for example "nmap -sP 192.168.0.*") inside our…
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Share one IP address with a simple router

We have just moved into a new office and have been given our 'internet connection' in the following form: One Ethernet cable in the corner of the room An IP address with subnet mask 255.255.255.0 We have several computers, and are wanting to set…
soothsayer
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Is it possible to cross-connect two AUI ports without transceivers?

Many Ethernet devices predating the ubiquity of RJ45 transceivers had DB15 "AUI" ports. One is ordinarily expected to attach a transceiver for either coaxial or twisted-pair Ethernet. Is it possible to cross-connect two AUI ports using an…
Skyhawk
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Understanding Ethernet Headers, What MTU Do I Need?

I see many articles on line stating that the overhead of Ethernet is 18 bytes (example: http://www.learnios.com/viewtopic.php?f=8&t=18887) Looking at this wiki article (http://en.wikipedia.org/wiki/Ethernet_frame#Structure) 18 bytes is the following…
jwbensley
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Why is half-duplex mode supported for 10BASE-T and 100BASE-TX networks?

I'm currently learning about Ethernet standards, auto negotiation and duplex mismatch. That made me wondering why half-duplex operations is allowed in 10BASE-T and 100BASE-TX networks. Wouldn't it have been easier to enforce full-duplex operation in…
aka
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The same driver for multiple network cards -- performance bottleneck?

I'm using driver e1000e for multiple Intel network cards (Intel EXPI9402PT, based on 82571EB chip). The problem is that when I'm trying to utilize maximum speed (1GB) on more than one interface, speed on each interface starts to drop down. For one…
ctinnist
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Solaris ethernet ports: nge2 and nge3 are missing

There is a Sun X4100 with an interface nge0 which is configured and working. The server has a group of 4 network jacks in the back and nge0 corresponds to ethernet port 0. I tried enabling ethernet port 3 with ifconfig nge3 plumb and I received the…
700 Software
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Windows packet sniffer

What packet sniffer would you recommend using, especially in a 50+ workstation environment? I am a fan of Wireshark but it's got quite a bit of security history. Is there something better?
Terry
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