Fibre Channel Jumbo Frames - UCS

I was wondering if it's actually possible to have Jumbo Fibre Channel Frames running on a UCS?
I've read these two articles which provide some excellent information on implementing Jumbo Frames and Fibre Channel Jumbo Frames:
http://datacenteroverlords.com/2013/04/01/jumbo-fc-frames/
http://www.ccierants.com/2013/10/ccie-dc-definitive-jumbo-frames.html
Everything within the SAN I'm administrating has the ability to set the MTU up to 9036 except for the UCS. For example on the NetApp gear I can set the MTU per interface, on the Cisco MDS I can set the MTU per vsan. However in the UCS manager when I go to QoS System Class, the option to set the MTU for Fibre Channel is greyed out and it doesnt look like there's anyway to override the preset frame size. I can set the MTU of Best Effort however my understanding is Fibre Channel traffic within the UCS will use the Fibre Channel system class.
Furthermore I noticed I can set the Maximum Data Field Size on the vHBA's within the UCS manager however my understanding is the maximum this can go up to is 2048.

Hi
Did you check
http://datacenteroverlords.com/2013/04/01/jumbo-fc-frames/
Erik Smith says:
April 1, 2013 at 5:52 pm
April fools! I wish I saw this earlier, I would have posted corroborating test results!
In Summary: forget Jumbo Frames for FC !

Similar Messages

Enable Jumbo Frame Support On UCS

Could someone direct me to the documentation for the proper way to enable jumbo frame support on UCS? I'm trying to troubleshoot a problem and have configured MTU of 9000 from ESX running on a blade to an NFS server off a Nexus 5k. I have good documentation for configuring jumbo frame support on the Nexus 5k and on ESX but nothing really specific for UCS.
For Nexus 5k:
http://www.cisco.com/en/US/docs/switches/datacenter/nexus5000/sw/configuration/nxos/Cisco_Nexus_5000_Series_NX-OS_Software_Configuration_Guide_chapter33.html#con_1150612
show run:
policy-map type network-qos jumbo
class type network-qos class-default
mtu 9216
system qos
service-policy type network-qos jumbo
For ESXi:
esxcfg-vswitch -m 9000 vSwitch0
esxcfg-vswitch -A IP_Storage vSwitch0
esxcfg-vswitch -v 31 -p IP_Storage vSwitch0
esxcfg-vmknic -a -i 10.254.31.2 -n 255.255.255.192 -m 9000 "IP_Storage"
Testing:
I have been able to ping (with large payload) the NFS host interface from a temporary vlan interface on the N5k. I cannot do the same to the ESX hosts or between hosts.
Thanks,
-R

Russell
What network adapter are you using? M81KR or the M71KR's or any other?
The MTU is set on a per CoS basis in UCS. If you do not have any QoS policy defined for the vNIC that is going to the vSwitch, then the traffic is going to Best-Effort Class. All you need to do to enable jumbo frames is to enter the MTU to be 9000 in the MTU pulldown for whatever class the traffic is going to.
Its also given in the user guide -
http://www.cisco.com/en/US/docs/unified_computing/ucs/sw/gui/config/guide/1.3.1/UCSM_GUI_Configuration_Guide_1_3_1_chapter18.html
MTU drop-down list
The maximum transmission unit for the channel. This can be:
An integer between 1500 and 9216. This value corresponds to the maximum packet size.
fc—A predefined packet size of 2240.
normal—A predefined packet size of 1500.
Note
This field is always set to fc for Fibre Channel.
--Manish

Enable jumbo frame on Nexus switch

I read following phrase in configuration guide of Nexus 5020
The Cisco Nexus 5000 Series switch is a Layer 2 device. This means it does not fragment frames. As a result,
the switch cannot have two ports in the same Layer 2 domain with different maximum transmission units
(MTUs). A per-physical Ethernet interface MTU is not supported. Instead, the MTU is set according to the
QoS classes. You modify the MTU by setting Class and Policy maps.
When you show the interface settings, a default MTU of 1500 is displayed for physical Ethernet interfaces
and a receive data field size of 2112 is displayed for Fibre Channel interfaces
Has anybody configured jumbo frame with above mentioned way ?

Yes, it looks something like this:
policy-map jumbo
class class-default
mtu 9216
policy-map class-default
class class-default
mtu 9216
system qos
service-policy class-default

Fibre Channel Storage

Im planning on using three mac pros to capture live footage in prores 422hq 1080i.
Can I put a fibre channel in each mac pro and network them to each other...that way when i edit i can just edit from each drive from one mac pro without having to copy them all to one station?

What you're asking is called arbitrated loop.
You can start from here:
http://en.wikipedia.org/wiki/Arbitrated_loop
My preliminary kinda lame and super-fast answer is that you'll be involved in a messy configuration, which isn't gonna worth the cost and time.
If you're gonna use fibre channel, buy a switch a proper SAN and do that. Otherwise it is possible to use Gigabit Ethernet switches, a mac pro as a host and work with ProRes.
If you're gonna use the MacBook pro, absolutely check if the GigE port supports jumbo frames because most new iMacs do not.

FTTH connection proper MTU Size and Jumbo frames

I've recently moved to a ISP that provides a 4mbps connection through FTTH(Single OFC). There is a EPON ONU in my premise from which a RJ-45 lan cable is connected to my Intel DH67CL1 board based PC. manual says, the NIC is a gigabit ethernet card. I tried setting MTU of 8996 and I can ping and browse fine. But, I'm totally in dark whether this value is optimum and works flawlessly browsing sites. How to find and set the proper MTU for a fibre network like this? Is the value correct?
I tried like this decreasing mtu value:
ifconfig eth0 mtu 8997
SIOCSIFMTU: Invalid argument
then,
ifconfig eth0 mtu 8996
^^^ No error message and it seems accepting.
BTW, from arch wiki, I saw that the driver module(e1000e which is used here) used by NIC have some bug report filed wr.to Jumbo frame. Am I doing things correctly? Earlier MTU was at default 1500. Please guide. thank you
Some drivers will prevent lower C-states
Some kernel drivers, like e1000e will prevent the CPU from entering C-states under C3 with non-standard MTU sizes by design. See bugzilla #77361 for comments by the developers.
https://wiki.archlinux.org/index.php/Ju … mbo_frames

yeah, i actually talked to support and they told me the same thing. just another example of misleading information from Linksys as here is what the manual and the help page say:
MTU
MTU is the Maximum Transmission Unit. It specifics the largest packet size permitted for Internet transmission. Select Manual if you want to manually enter the largest packet size that will be transmitted. The recommended size, entered in the Size field, is 1500. You should leave this value in the 1200 to 1500 range. To have the Router select the best MTU for your Internet connection, keep the default setting, Auto.
no where in that description does it say that 1500 is the maxmium.
because this is also a gigabit switch, one would expect that jumbo frame support is not out of the realm of possibility. as a point of reference any other $50 (or less) gigabit switch supports this, but that's what i get for expecting too much from Linksys.
thanks for the info.

Jumbo Frame issue

I have a iMac late 2008, a lot of times (generally every OS upgrade, minor and major) that I try to use the jumbo frame, every time with the same result: for one our or two it works well, after the LAN stuck, I have to pull off and plug-in the cable in order to unstuck the LAN.
I use NFS in order to store in the NAS the Virtual Machine and they fly with jumbo frame, 2 or 3 times faster then without.
I tried to fix the speed, the half or full duplex but the result are always the same, like a time bomb!
Why that's happen? Have anyone any idea?

Hi,
In the end, it turned out to be that the port-channel interface on the Dell did not have jumbo MTU set. I did the following to set it:
config
interface port-channel 1
mtu 9216
end
copy run start
At that point, both interfaces in the port channel got shutdown for some reason, the 7120 showed its 2 SAN interfaces as down too.
So, I did a:
no shutdown
When the interfaces and port-channel came back up, I was able to vmkping -d -s 8972 to the target IP address, and from windows a ping -f -l 8972 worked. I am able to scan and see iSCSI targets now.
Edited by: ziffsis on Jan 31, 2013 10:51 AM

Jumbo Frame iSCSI

I am using iSCSI for backup to disk. The target is SUSE 10 and initiator
is NW 6.5 sp7. The speed isn't so great, so I'm trying to make sure I've
got Jumbo frames setup properly. I've added the switch Jumbo=9000 to my
netinfo.cfg file, as per a post here by Massimo from 15-Aug-2007.
So the load network card line looks like this:
LOAD B57 NAME=B57_1_EII_EII FRAME=Ethernet_II SLOT=10019 Speed=AUTO
RxBuffers=200 Jumbo=9000
But when I look in Monitor > LAN/WAN Drivers the Jumbo Packet Size
(bytes) still reads 0. So, I don't think I'm getting Jumbo frames happening.
I've also set the following:
TCP delayed acknowledgement =on
tcp nagle algorithm=on
tcp minshall algorithm=on
set tcp maximum inital receive window = 64
and in startup.ncf
set maximum physical receive pacet size = 1800
Can anyone help me figure this out?
Thanks,
Doug

Massimo Rosen wrote:
> Hi,
>
> Doug wrote:
>> I am using iSCSI for backup to disk. The target is SUSE 10 and initiator
>> is NW 6.5 sp7. The speed isn't so great, so I'm trying to make sure I've
>> got Jumbo frames setup properly. I've added the switch Jumbo=9000 to my
>> netinfo.cfg file, as per a post here by Massimo from 15-Aug-2007.
>>
>> So the load network card line looks like this:
>>
>> LOAD B57 NAME=B57_1_EII_EII FRAME=Ethernet_II SLOT=10019 Speed=AUTO
>> RxBuffers=200 Jumbo=9000
>
> That looks good. Yre you sure this is the first load line for that nic?
>
>
>> Can anyone help me figure this out?
>
> Well, you already got the question about your switch, but what about the
> Target? Are you sure it can really do Jumbo Frames? If all else fails,
> take a lan trace of a tcp connection setup, and you wil see which frame
> size is advertised by each side.
>
> CU,
Yes the target is doing jumbo frames. I set the MTU to 9000, and the
Windows box saw a good improvement on speed.
Here's the netinfo.cfg file.
#!VERSION=2.3
#! --- WARNING -- WARNING -- WARNING -- WARNING -- WARNING -- WARNING ----
#! This file was created by the Internetworking Configuration Console.
#! It is intended to be modified ONLY by the configurator (INETCFG.NLM).
#! Tampering with this file may cause severe malfunctioning of the system.
#! The configurator will check for tampering and abort if it is detected.
#!SERVERTYPE=NORMAL
#!UIMODE=NORMAL
#!BEGINGENLOAD
LOAD SNMP
LOAD BCALLSRV
#!END
#!BEGINTSMLOAD
#!END
#!BEGINBOARD DRVR=B57 NAME=B57_2_EII STATUS=ENABLED NUMPORTS=1
DRVRTYPE=LAN VARIABLEPORTS=NO PORTPARAM=CHANNEL SLOT=10020 Speed=AUTO
RxBuffers=200
#!BEGINPORT NAME=B57_2_EII NUMBER=1 STATUS=ENABLED FRAMES=YES NUMLINKS=0
MEDIA=EtherTsm WANFRAME=UNCONFIGURED
#!REFCOUNT=1
LOAD B57 NAME=B57_2_EII_EII FRAME=Ethernet_II SLOT=10020 Speed=AUTO
RxBuffers=200 Jumbo=9000
#!END
#!END
#!BEGINBOARD DRVR=B57 NAME=B57_1_EII STATUS=ENABLED NUMPORTS=1
DRVRTYPE=LAN VARIABLEPORTS=NO PORTPARAM=CHANNEL SLOT=10019 Speed=AUTO
RxBuffers=200
#!BEGINPORT NAME=B57_1_EII NUMBER=1 STATUS=ENABLED FRAMES=YES NUMLINKS=0
MEDIA=EtherTsm WANFRAME=UNCONFIGURED
#!REFCOUNT=1
LOAD B57 NAME=B57_1_EII_EII FRAME=Ethernet_II SLOT=10019 Speed=AUTO
RxBuffers=200 Jumbo=9000
#!END
#!END
#!BEGINPROTO PROTO=TCPIP STATUS=ENABLED
LOAD Tcpip RIP=No Static=Yes LoadSharing=No Forward=No VIPASupport=No
#!BEGINBIND STATUS=ENABLED
BIND IP B57_2_EII_EII ADDRESS=xxx.xxx.xxx.xxx MASK=255.255.255.0
#xxx.xxx.xxx.xxx
#!END
#!BEGINBIND STATUS=ENABLED
BIND IP B57_1_EII_EII ADDRESS=xxx.xxx.xxx.xxx MASK=255.255.255.0
#xxx.xxx.xxx.xxx
#!END
#!END

Xserver Fibre Channel with tape backup issues?

Is this correct, that OS X 10.4.9 and 10.4.10 has a fibre channel issue with external tape drives (as well as SCSI drives)???
And this is to be fixed in 10.4.11? Do we have a time frame when we will see 10.4.11 to fix this major snafu?
I'm going to decide on a different server (in the meantime) and do net backups if this is the case. But what about others that run backup off the server, attached to an Xserve RAID?
BTW, I contacted BRU support with query on their software...I give kudos to them. Their support is spot on!
Message was edited by: Eddie Ski

Retrospect is just hideously, egregiously out of date and I don't think EMC gives a d*mn, at all.
Even pre-Intel, it will happily LOCK up your server while failing to properly time out when trying to talk to a tape library. It's well-known, Retro + Tape Library = h*ll on earth. And the fault lies squarely with Retro because something like Bru and other more expensive software does not have the same issue.
So let's just make sure -not- to judge "SCSI" isues in OS X based on the ungodly-awful behaviour of Retrospect. Might as well do automobile performance tests using only amateur drivers ; )

No jumbo frames between 4500-X and Force10

Hi,
We have just installed new Cisco 4500-X 10Gbe SFP+ switches.
We have Dell Blade Chasis with Force 10 MXL blade switches.
We are testing/preparing the environment before our new Dell compellent hybrid arrays arrive, but we face a problem with Jumbo frames between the Cisco 4500-X and the Dell Force10.
When I do a ping -L from the blade server to a host connected to the Cisco 4500-X anything bigger then 1472 bytes seems to get dropped.
When performing a ping between servers connected to the 4500-X I can use jumbo frame sizes like 9000 without issues
When performing a ping between servers in the blade chassis I can use jumbo frame sizes like 9000 without issues
Now we also have a pair of Cisco 3750X switches that are currently being used for Dell Equallogic 1Gbe SAN and they are connected to the same Force10 switches as the 4500-X are and I have created the exact same LACP port-channels between the Force10/3750X as for the Force10 4500-X. Jumbo packets to the 3750X is working fine but for the 4500-X it is not.
I have tried connecting the switches simply on access port level, creat a vlan trunk and create a portchannel with trunking but none of the solutions seem to work, in every situation packets above 1472 are dropped... at least they dont arrive at the destination.
On every port of the 4500-X the MTU is set to 9198, the vlan each port is in is set to 9198 and the port-channel is set to 9198
System MTU can only be set to 1550 so that is on default 1500 altough I tried setting it to 1550 but that didnt make any difference ofcourse.
The 4500-X is running version 03.04.04 SG / 15.0(1sr) SG10
The Force10 is running 9.6.0.0
Any help is appriciated

Sorry for the delay , i have bought the 3064-32T , it seemed more cost effective as the transceivers are so expensive and it has more ports too.

Can I disable the B200 blade Fibre Channel vHBA's

Hello
I am configuring my service profiles for my B200 blades and was wondering if there was a way to disable the Fibre Channel HBA's. I will not be using FC as all my storage is iSCSI.
Thanks
Mal

my comment:
1) if he doesn't require FC, don't configure it in the service profile !
2) can you please give us a pointer, where disabling a vhba in 2.2.3 is documented. I checked
http://www.cisco.com/c/en/us/td/docs/unified_computing/ucs/sw/gui/config/guide/2-2/b_UCSM_GUI_Configuration_Guide_2_2/b_UCSM_GUI_Configuration_Guide_2_2_chapter_01.html
Table 3 New Features and Changed Behavior in Cisco UCS, Release 2.2(3)
and can't find it.

Aggregates, VLAN's, Jumbo-Frames and cluster interconnect opinions

Hi All,
I'm reviewing my options for a new cluster configuration and would like the opinions of people with more expertise than myself out there.
What I have in mind as follows:
2 x X4170 servers with 8 x NIC's in each.
On each 4170 I was going to configure 2 aggregates with 3 nics in each aggregate as follows
igb0 device in aggr1
igb1 device in aggr1
igb2 device in aggr1
igb3 stand-alone device for iSCSI network
e1000g0 device in aggr2
e1000g1 device in aggr2
e1000g2 device in aggr3
e1000g3 stand-alone device of iSCSI network
Now, on top of these aggregates, I was planning on creating VLAN interfaces which will allow me to connect to our two "public" network segments and for the cluster heartbeat network.
I was then going to configure the vlan's in an IPMP group for failover. I know there are some questions around that configuration in the sense that IPMP will not detect a nic failure if a NIC goes offline in the aggregate, but I could monitor that in a different manner.
At this point, my questions are:
[1] Are vlan's, on top of aggregates, supported withing Solaris Cluster? I've not seen anything in the documentation to mention that it is, or is not for that matter. I see that vlan's are supported, inluding support for cluster interconnects over vlan's.
Now with the standalone interface I want to enable jumbo frames, but I've noticed that the igb.conf file has a global setting for all nic ports, whereas I can enable it for a single nic port in the e1000g.conf kernel driver. My questions are as follows:
[2] What is the general feeling with mixing mtu sizes on the same lan/vlan? Ive seen some comments that this is not a good idea, and some say that it doesnt cause a problem.
[3] If the underlying nic, igb0-2 (aggr1) for example, has 9k mtu enabled, I can force the mtu size (1500) for "normal" networks on the vlan interfaces pointing to my "public" network and cluster interconnect vlan. Does anyone have experience of this causing any issues?
Thanks in advance for all comments/suggestions.

For 1) the question is really "Do I need to enable Jumbo Frames if I don't want to use them (neither public nore private network)" - the answer is no.
For 2) each cluster needs to have its own seperate set of VLANs.
Greets
Thorsten

Mid 2010 Macbook Pro - Change MTU size kills internet (Jumbo Frames)

Hi everyone, i'm hoping someone here can enlighten or help me solve my problem I'm having.
I am trying to change my MTU size to enable Jumbo frames on my 13 inch Mid 2010 Macbook Pro. I recently bought a ReadyNAS Ultra and would like to speed up transfers to the unit.
My setup is as follows:
I have my ReadyNAS Ultra 2 and 2010 Macbook Pro (Core 2 Duo) wired via cat6 ethernet to my 5th Generation Apple Airport Extreme. The Airport Extreme is connected via cat5e to my AT&T Uverse Gateway which is set up to allow my Airport to assign DHCP and NAT (gateway is in bridge mode with wireless off).
Anyways, I have enabled Jumbo frames on my ReadyNAS, when I enable them on my MBP.. it applies fine. It disconnects / reconnects the ethernet like it should, but then my connection drops. I can't see any devices on my LAN and I cannot access any internet websites, but according to the network pane I am still assigned a valid dhcp address. When I manually try to increase my MTU size, the same thing happens (from 9000 to 1600 I tried every size).....
Could it be my MBP just can't suppose the increase of MTU size? It leaves them at 1500 when I set it to automatic... if it doesn't support the increased MTU size, why would it let me custom change the MTU and even give an option to select "Jumbo Frames (9000)"?
I appreciate any help in advance!!

asdftroy wrote:
If you did read my post then you would have saw that the option is there, but that is not entirely what my inquiry is about. The option isn't working as intended, and I was wondering if anyone had the same issues as me. Thanks anyways.
Anyone else?
The way you responded to someone trying to help you probably means others will be hesitant to try.

Clarification on how to use Xserve Raid and Fibre Channel without xsan.

First let me apologize for not responding earlier to your response, I tend to get busy and then forget to check back here.
Tod, the answer to your question is No, only one computer is accessing the xserve raid files at any one time and that is via Fibre Channel. However I do have the xserve raids set up as share points via ethernet.
Maybe I should turn that off and only access the files with the one computer that can connect via fibre channel.
I never thought of that. I will try that while I await for your answer, thanks again.
Todd Buhmiller
I have the following setup:
Xserve: 2x2Ghz Dual Core Intel Xeon, 5Gb of Ram, Running 10.5.8 Leopard Server
Xserve Raid with firmware version 1.5.1/1.51c on both controllers, and
Qlogic Sanbox 5600
Apple Fibre Channel Cards in Xserve, and Mac Pro Tower; Apple 2 Port 4Gbs Fibre Channel Card
Mac Pro Tower-Quad Core Intel Xeon 2.8Ghz, 16Gb of Ram, Running Snow Leopard 10.6.4
Here is the problem.
The directory for the xserve raids keep getting corrup, and I use disc warrior to rebuild them. Is there a way to keep the directories from getting corrupt? I am a few pieces of equipment before I can build an Xsan as that is the ultimate goal, but until then, I just need to be able to have the raids funciton as storage without having to rebuild the directories all of the time.
Anybody have any suggestions?
Thanks
Todd Buhmiller
Widescreen Media
Calgary, Alberta Canada
Tod Kuykendall
Posts: 1,237
From: San Diego
Registered: Oct 11, 2000
Re: Xserve Raid Mounts, Corrupt Directory tired of rebuilding directory
Posted: Jun 27, 2010 1:25 PM in response to: Todd Buhmiller
Are multiple computers accessing the same data on the RAID at the same time?
If so then NO. This is the source of your data corruption and I'm surprised if you were able to get all your data back every time if this is how you've been running your system. Each fibre channel assumes it has full and sole control of every volume it has mounted, no data arbitration is practiced and data corruption will occur if this assumption is wrong.
The only way this set-up will work is to use partitions or LUN masks so the volumes are accessed by one computer at any time. As long as one computer relinquishes control before another mounts it you will dodge arbitration issues but this is a dangerous game. If you screw up and mount an already mounted volume - and there is no easy way to tell if a volume is mounted - corruption will then occur. Sharing data simultaneous at fibre speeds is what XSAN does and to do this you need it.
HTH,
=Tod
Intel Xserve, G5 XServes, XRAID, Promise

+The xserve raids will mount automatically to any computer that I connect the qlogic fc switch to+
This is source of the corruption to your data. Any computer that attaches to a drive/partition via fibre channel assumes that it alone is in control of the drive and data corruption is inevitable.
+Is that the issue, should I disconnect the xserve from the fc switch and leave it connected via ethernet?+
Short answer: YES. The ethernet connections are fine because the server is controlling the file arbitration through the sharing protocol. Fibre channel connections assumes complete control over the partition and no arbitration of the file access is performed. It's like two people independently driving trying to drive the same car to different locations.
Depending on your set-up it is possible for the two machines to see and use different parts of the Xserve RAID storage but they cannot access the same areas without SAN doing the arbitration.
Hope that's clear,
=Tod

Can I hook up a NAS via Fibre Channel?

I am building a Linux NAS to be accessed by my Macs. I've purchased fibre cards for all of my macs, an LSI fibre card for my Linux machine, and a McData 4400 fibre switch. I'm trying to configure my fibre network so I can share files from my NAS. I've got the fabric set up, but everything that I read is talking about using SAN software to connect to a SAN, not a NAS. I can't find any information at all on how to do what I want to do, or whether or not it's possible. Can someone please help me figure out how to set up this Fibre Channel network, or at least figure out if it's possible or not? Thank you!
-Ryan

Is what you want technically possible? Probably.
In an earlier era, you could have a network or an image scanner or other devices connected to a host via SCSI; via a storage bus. There was all manner of odd SCSI-connected gear. (Think of SCSI as expensive multi-host USB with big expensive cables and with expensive peripheral devices, and you'll have the general idea. And FWIW, SCSI is the underpinnings of USB.)
You would end up writing a whole lot of driver code for the devices and hosts you have, too.
Which is where folks end up with commercial SAN solutions, or with NAS solutions, and not with using a SAN as a network.
The various Fibre Channel controller vendors discussed but never seemed to have sorted out the network interface designs for their FC controllers.
If you want to roll your own storage arrays akin to the [Apple Xsan|http://www.apple.com/xsan> or the HP [MSA|http://h18000.www1.hp.com/storage/diskstorage/msa_diskarrays/sanarrays/index.html] or [EVA|http://h18000.www1.hp.com/storage/diskstorage/eva_diskarrays/evaarrays/index.html] SAN arrays, well, have at. You'll likely end up needing to write host disk drivers, as well as the firmware within the SAN controller. Networking drivers might be a bit more tricky; I haven't looked at those device interfaces in a while, and you'd need to tie those drivers into the host network stacks. Once you have some or all of that working, then the hosts can see the block storage out on the SAN. If you need sharing, you'll need to sort out a cluster or SAN file system to run atop the block storage or atop the network connection you've built; a file system that can coordinate distributed access.
Possible? Sure. On a budget? Probably not.

Routers: What Are Jumbo Frames and why do I need them?

Some routers' specs specifically mention that they handle jumbo frames (with a number like 9K). I have a network with 2 iphones, two ipads, 4 computers, two networked Blu-Ray players, and 3 computers, all of which are operating simultaneously a lot of the time.
Some other companies seem to be using the fact that they support jumbo frames as part of their selling points. How do they help?
I asked Cisco Chat support about the RVS4000 and whether it supported them on both the WAN and the LAN. They said not on the WAN. They also said "
It appears under the L2 Switch tab you can input a Max Frame type.....
I don't see anything that actually says jumbo frames but I believe you can put in a value.....
after the device is setup you can navigate to the L2 Switch option and it has a Max Frame value"
I'm not sure whether this router supports jumbo frames or not. I have a short list of wired gigabit routers that I'm considering for purchase and the RVS4000 is on the list.
I need to learn more about this topic so any help or pointers to stuff to read would be greatly appreciated.

Thanks so much for the info. I read virtually all of it. The Jumbo Frames thing sounds very tricky - and possibly detrimental. I'll have to see if Time Warner Roadrunner supports them and at what sizes. Other than for really big file transfers between machines on my network (which I don't do that often) it sounds like jumbo frames isn't going to do much for me.
It also looks like the RVS4000 is not what I want. The smallnetbuilder review was a very useful one-although it's 4 yrs old, it's still likely mostly valid.
I do some gaming at times and it sounded like the adjusting of frame sizes until all the devices in the path are the same can cause unacceptable latency. Now it seems that no matter which gigabit router I choose, I need to be sure I get one where I can disable the major frames process, and maybe enable it when I want to do hard drive backups across the network. Welcome to the gigabit ethernet world I guess.
The RV220W sounds like a nice machine, but is a lot more machine than I think I need for my network. I read a very detailed review of it on Amazon at: http://www.amazon.com/gp/cdp/member-reviews/A2BBGBR6ARRJQO/ref=cm_pdp_rev_more?ie=UTF8&sort_by=MostRecentReview#R2SCJUQOKY7EN
It also sounds like it's more complex to set up than I would like to tackle. I'm a retired electrical engineer but definitely not a skilled IT person, so plug and play simplicity is important. I understand just enough to get in trouble.
Thanks again for the links. Much appreciated.

Fibre Channel Jumbo Frames - UCS

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