Any real advantage of running gigabit between servers???

[Stooo]

Hello all. Hope everyone is ready for the upcoming holidays!
My question is at my job we recently upgraded our PDC and when it was switched out the gigabit port was not used, instead it was plugged into a 100mb port. My boss who knows absolutely everything to know about any and every computer ever made or yet to be made said that after moving the server off a 100mb line to a gigabit port that the backups will be much faster like half the time of a 100mb. I did not think it would be too much of a difference because of limitations on our servers (or any server for that matter). Is it wise to use gigabit between just the servers or should we be useing gigabit to our switches elsewhere inside our LAN???
There are
Three Dell POWEREDGE
One IBM (PDC)
One IBM Terminal server
One IOMEGA NAS server
We have some el cheapo 3COM superstack 48 port 10/100 switches and a bunch of little pos workgroup switches around where we ran out of ports. All the stuff predates me but I thought it would be best to run the gigabit between switches so the bandwidth available to our users would be higher. We primarily use the network for database access and file sharing.

[NateX]

As long as the servers are all on a Gigabit segment, yes it will speed things up - especially if you are doing network backups. You don't really have enough specific information to give an informed answer. I can say that I have set up a few small to medium-sized networks using 10/100 24 and 48 port switches with a couple GB uplinks, and I always plug the DC into the Gigabit port. Even if all the other machines on the switch are connected at a slower speed it gives the server more bandwidth.

For example, a server plugged in at 10/100 would become bandwidth saturated as soon as one machine plugged into the switch established a connection to transfer a large amount of data at full speed. If the server was connected at GB speeds however, it would take roughly 10 machines running at 10/100 to max out it's connection. Keep in mind this is a generalization as there are a lot of other factors that would affect this as well.

The backplane (where all the ports connect to) of a switch is typically capable of several times the badwidth of an individual port on the switch, and SHOULD be capable of handling traffic for every port operating at full wire speed, though this is not the case with cheaper switches.

Hope this helps somewhat.

[SunKing]

NateX speaks the truth.

I just thought I'd add a couple of details. It also depends on the speed which your backup server/system can recieve data and the number of concurrent backups running.

Even so, a 100Mbit network throughputs very approximately 10 megabytes per second, which any decent server can outperform these days. I would definately recommend having a gigabit backbone.

[SRTDodge05]

No question about it, gigabit is 10X faster then 100mb. All server should run gigabit and clients at 100mb that way clients wont overload the servers. I run all gigabit in my house and it flys.

100mb you get around 10-15mb/sec
gigabit you get around 45+mb/sec

Im averaging 70mb/sec with my network setup.

[shaihulud]

When at gigabit speeds, host to switch and switch to host, you are basically limited to the ability of the sub-system and hard drive of the host that is transferring bits and equally the same to receive and write the bits. The most that ever can be seen at 100Mb tops at around 12MB/s with protocol overhead included. Gigabit can be more than this at about 120MB/s.

However, mixing will not be as beneficial. The packets will be sent to the switch at 1Gb speed but the switch will send the packets, in a buffered transfer, to the receiving host at 100Mb speed. The ability of the network capacity for packet processing is more based on the core logic(s) and orientation of packet processing of the networking device. The ability is or usually can be found for more business type equipment. Dell, for example, will state packets per second or your forwarding rate for their switches. This is part of your true measurement of when it is “maxed out.” Because, one host can send the majority of the packets per second than all combined hosts attached to the switch. You can easily be bottlenecked with lesser switches when traffic is propagating and transferring. Unfortunately, you will not see or may not see this information with SOHO routers/switches and switches.

[Stooo]

shaihulud, spoken like a network specialist... The topology was one server at gigabit speed the rest were not. The LAN was in two segments and the trunk was 100mbit between two switches, for me the performance of having the two connected on gigabit seemed more bang for the buck.... Anyhow the backups still took the same amount of time as before even after doing the entire LAN at gigabit speed.

Since this was my first IT position I was unsure as to whether my boss had any clue as to what he was referring to and after everything I've seen... I'm sure he doesnt. LOL

Just have to add alittle more to this I had to upgrade the NICS in all PCs to gigabit, at the same time we had a remote office being setup with two T1 lines for phones and customer service PCs... He made me install gigabit NICs in their PCs even though they are only coming across the two T1 !!!!

Did I mention he ordered 60+ MultiMode FIBER NICS ???? LOL

[shaihulud]

I would recommend, if using UNIX, Linux, or Windows Server 2003, NIC’s that support RSS (Receive Side Scaling). This is as long as you are using multiprocessor or multicore technologies for the host/server. Here is a document from MS about the subject matter: http://www.microsoft.com/whdc/device.../NDIS_RSS.mspx

When the network can actually exceed the ability of the host system(s) and its intrinsic characteristics, you will see different bottlenecks and limitations. Usually, this, the host system and its hardware, is the limiter of the network when an excellent infrastructure is implemented.

LAN traffic will always be more than WAN traffic. So, his thinking is correct at least in this manner, and you should be appreciative! All too often the thinking and IT budget is in asinine reverse. Cutting corners without a technical thought or even a baseline to prove the reasoning for it.

Now, if he ordered the multimode fiber NIC’s, is he going to order the supporting fiber infrastructure? Curious, what NIC’s did you install and what make are the fiber supporting NIC’s? Personally, my recommendation even in small to most large business I would recommend Intel’s Ethernet logics. Affordable cost, excellent if not on par performance, extensive driver base, commendable documentation, and excellent support. Also, with particular core logics from Intel you can have support for Intel’s I/O Acceleration (http://www.intel.com/technology/ioac...ion/index.htm).