Help Understand Jumbo Frames

I was hoping to get help in understanding jumbo frames. I have the following setup in our network. If host 1 sends a jumbo frame to host 2 what will happen on the switch. The SVI VLAN 10 has the MTU of 9216 and the SVI VLAN 11 MTU is 1518. Will the switch fragment the packet to 1518 bytes when it send the traffic to host 2?

Disclaimer
The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.
Liability Disclaimer
In no event shall Author be liable for any damages whatsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.
Posting
As your OP described two VLANs, which usually implies different subnets, and the need to route between them, Charles' second sentence would apply.

Similar Messages

  • Help Understanding Jumbo Frames

    I am trying to understand jumbo frames and want to understand what happens in the following scenario. I have two VLANs configured on a switch.
    VLAN 10 has mtu 9216 enabled on the SVI interface. The other VLAN is 11 and it has a mtu of 1518 on the SVI interface. if a host in VLAN 10 sends a jumbo packet of 9216 to a host in VLAN 11 which only supports a mtu of 1518 what happens on the switch. Will the switch fragment the 9216 packet into 1518 byte packets?
    Thanks

    Disclaimer
    The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.
    Liability Disclaimer
    In no event shall Author be liable for any damages whatsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.
    Posting
    As your OP described two VLANs, which usually implies different subnets, and the need to route between them, Charles' second sentence would apply.

  • 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.

  • Airport Extreme with Gigabit Ethernet - Does it have jumbo frame support?

    Please, can I get definite answer to this question? I do not need speculations as I read some reviews already. Can we have Apple finally put complete specification of the product rather than "popular one" with attachement of protocol numbers?
    I just need simple answer possibly from Apple engineering team to the following questions:
    1. Does current Airport Extreme have support for jumbo frames (everything above 1500bytes per frame)? (if one does not know what that is them perhaps understanding acronym "MTU" can help a bit)
    2. If there is support then what is the maximum supported size of jumbo frame? (Some products do not go above 6k and I read some statistics that traffic somwhere is usually 66% at about 4k jumbo frames and above that there is not much...)
    3. If there is no support then does Apple plan on update for this (firmware or hardware) in the future?
    Please, do not tell me that someoene ran something with jumbo frame and it worked as I tried yesterday LaCie Ethernet drive with supposedly setup (I set it myself) of jumbo frame 4k and on soft reboot of the drive it worked when connected to Airp[ort Extreme, but after hard reboot the disk is not visible anymore. I will recover the disk, but I need to understand if I have chance of using jumbo frames that tremendously improve performance with large files (e.g. try movies stored for AppleTV on network drive) when using Airport Extreme with its gigabit Ethernet... or that is just Gigabit Ethernet for product marketing purposes only.
    I just need reliable answer by product specification that should be on paper at Apple, but it is not so I hope that one of guys here has access to some engineering team.
    Thank you,
    Maciek Samsel

    The spec. on the chip used by Apple support your conclusion.
    BCM5395 Features
    Complies with IEEE802.3, IEEE802.3u, IEEE802.3ab standards
    5 10/100/1000Mbps Auto-Sense RJ45 ports supporting Auto-MDI/MDIX
    All ports Support Full/Half Duplex transfer mode for 10/100Mbps and Full Duplex transfer mode for 1000Mbps
    Port-based and MAC-based VLAN
    IEEE 802.1Q-based VLAN with 4K entries
    Port-based rate control
    Port mirroring
    Compact field processor (CFP)
    512 rules
    Filtering, classifications, remarking, and priority actions.
    Priority modification on egress
    DOS Attack Prevention
    Loop detection for unmanaged configurations with Broadcom’s patented LoopDTech™ technology
    CableChecker™ with unmanaged mode support
    Double tagging
    IEEE 802.3x programmable per-port flow control and back pressure, with IEEE 802.1x support for secure user authentication
    4K entry MAC address table with automatic learning and aging
    128-KB packet buffer
    128 multicast group support
    Jumbo Frame support up to 9728 byte

  • *****Jumbo frame on colapse core****

    Hi Folks,
    I have been thinking and research about for that a while now, and yet i have not gotten a formal answer... Please read carefully...
    We are a medium size company.... In both our our remotes, we have four 3750G(two of them are 3750X) in a stack. All good there, the nightmare is we have everything single thing(pc,printer,phones,ipcam,servers(running esxi),SAN(storageFlex)) connected to the stack;therefore, the stack switches are acting as core,distribution and access layer at the same time.
    I need to enable jumbo frame to speed up back, isci frame between SAN and ESXi hosts. knowing i can only enable jumbo frame globally. Since i have all these devices connected to the stack which aren't supported jumbo! should i go head enable jumbo on the stack? Will the device which aren't support jumbo frame will continue to work? Or since i know interface with 100Mb and less will ignore jumbo, should i set all device for which i don't jumbo frame to 100Mb?
    Any help and suggestion will be greatly appreciate.
    Thanks,

    Disclaimer
    The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.
    Liability Disclaimer
    In no event shall Author be liable for any damages whatsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.
    Posting
    A device that doesn't support jumbo on a port that does, will work fine as long as another device doesn't send it a jumbo frame.  If that happens, the device will be unable to process the received jumbo frame.  (I.e. a jumbo enabled switch can allow MTU mismatch between hosts.)
    (If you're thinking about IP fragmentation, that will only happen across a L3 hop, and it often creates additional performance issues.)
    BTW, on the 3750 series, data transfer performance problems are often caused by default 3750 buffer allocations.  Allowing jumbo doesn't address that.  I.e., you might obtain much be better data transfer performance via buffer tuning.

  • SRW2048 and Jumbo frames

    I have a Cisco SRW2048 (Firmware 1.2.2d, boot 1.0.0.05) on which I have enabled jumbo frames but yet when I attempt with a Windows 2003 server to ping the mgmt IP of this switch with a frame over 1472 (ping -f -l 1472 w.x.y.z) I get a response of "Packet needs to be fragmented".  The server is connected to a Netgear gig switch (GS724AT) that has jumbo frames enabled and working as I can talk to other devices using jumbo frames.  Attempts to access the SRW2048 switch fail on packets larger than 1472.  I have also attempted a Windows 7 box using jumbo frames to no success.  The Windows 7 box works when connected to the Netgear switch but when I move the connection back to the SRW2048, jumbo frames on the windows box stop working.
    Any help or suggestions would be appreciated.
    Thanks.
    David

    On the SF-300 and SG-300 for Jumbo to work the Enable Jumbo checkbox must be unchecked. Either I don't understand Cisco logic or it's a bug in the GUI.

  • 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.

  • Adding jumbo frame support into an existing Ethernet network

    I have a remote site with 40 users that connect back to our main site via two point to point T-1’s. These users connect to an Exchange server (DMZ), Sybase databases on Sun servers (Internal network), and access the Internet via the main site.
    I have installed a new WS-2970G-24TS-E switch into the network at this remote site. I have connected all of the designers (total of 10) Apple G5 workstations and two Apple Xserve’s to this switch. I have also configured the “system jumbo MTU” to 9000 bytes on the 2970. I have not yet enabled jumbo frames on the Xserve’s or the G5’s since I am unsure of what the effect on the network might be. I imagine it could range from dropped packets to crashing the router.
    I would like to enable jumbo frame support on these devices since they transfer hundreds of gigabytes of data on their local network. But if I do this, what will be the affect when they attempt to visit web sites or connect to the Exchange server?
    How have you guys worked with this type of scenario?
    The address space for this site is a /25 of one of our class C’s.
    Please see the attached Visio diagram that outlines the connection points throughout the network.
    Thank you

    Best practice here is to segment your Jumbo Frame servers on their own VLANs for Jumbo supported systems only.
    As a post here has already mentioned, Path MTU discovery will tell the systems on the Jumbo VLANs to keep the frames under 1500 when talking to a non-Jumbo VLAN.
    http://www.cisco.com/univercd/cc/td/doc/product/lan/cat2970/12225see/scg/swint.htm#wp1154596
    Please rate all helpful posts.
    Brad

  • Jumbo Frames within Solaris 10 zones and multiple interfaces...

    We have Jumbo Frames working in the Global Zone, and have the MaxFrameSize=3,3,3 etc...
    We also have our AGGR's built correctly and defined aggr1:1 and aggr1:2
    the problem is on boot-up, if all the name files (hostname.aggr1 and hostname.aggr1:1) are defined in the /etc directory, then you can't start the zones....?
    and if you place the files in the /export/zones/<machinename>/root/etc/ directory, than the interfaces do not start-up automatically..... ?
    So If I want all the interfaces in the global zone to be seen by the other zones, and for the interfaces to come live when the zones are booted.... where do the hostname.interface files live....???

    Darren:
    I understand where you're coming from from a technical perspective. But there is a way you could work around it.
    For argument's sake, zones a+b with e1000g0 - e1000g3
    From an implementation perspective, what's to stop you from:
    e1000g0 / e1000g1 shared between all
    e1000g2 plumbed at global, only assigned to zone a.
    e1000g3 plumbed at global, only assigned to zone b.
    You can certainly have an empty interface file (i.e. cp /dev/null /etc/hostname.e1000g2 ; cp /dev/null /etc/hostname.e1000g3). The interface will plumb but have no IP information configured.
    This doesn't give truly exclusive interfaces to either zone, but it operates effectively as though it were.
    Warning: I haven't actually tested this, but I see no reason that it wouldn't work.

  • 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.

  • How do I maximize LAN speeds using Gigabit Ethernet, jumbo frames?

    I move a lot of large files (RAW photos, music and video) around my internal network, and I'm trying to squeeze out the fastest transfer speeds possible. My question has to do both with decisions about hardware and what settings to use once it's all hooked up.
    This is what I have so far:
    -- imac 3.06GHz, macbook pro 2.53GHz
    -- Cisco gigabit smart switch capable of jumbo frames
    -- Buffalo Terastation Duo NAS (network attached storage), also capable of Gbit and jumbo frames
    -- All wired up with either cat6 or cat53e.
    -- The sizes of the files I'm moving would include large #s of files at either 15MB (photos), 7MB (music), 1-2GB (video) and 650MB (also video).
    -- jumbo frames have been enabled in the settings of the macs, the switch and the buffalo HD.
    -- I've played with various settings of simultaneous connections (more of a help with smaller files), no real difference
    -- Network utility shows the ethernet set to Gbit, with no errors or collisions.
    -- have tried both ftp and the finder's drap and drop
    -- also, whenever I'm doing a major move of data, I kick my family off the network, so there is no other traffic that should be interfering.
    Even with all that, I'm still lucky to get transfer speeds at 15-20mbps, but more commonly at around 10. The other odd thing I've encountered while trying to up my speeds, is that I might start out a transfer at maybe 60mbps, it will maintain that for about 30-60sec and then it appears to ramp itself down, sometimes to as low as 1-5mbps. I'm starting to think my network is mocking me
    I also have a dual band (2.4/5) wireless n router (not jumbo frame capable), but I'm assuming wired is going to trump wireless? (NOTE: in my tests, I have disabled wireless to force the connection through the ethernet).
    Can anyone help with suggestions, and/or suggest a strong networking reference book with emphasis on mac? I'm willing to invest in additional equipment within reason.
    Thanks in advance!
    juliana

    I'm going to pick and choose to answer just a few of the items you have listed. Hopefully others will address other items.
    • This setup was getting me speeds as high as 10-15MB/sec, and as low as 5-6MB/sec when I was transferring video files around 1-2 GB in size
    I would think a single large file would get the best sustained transfer rates, as you have less create new file overhead on the destination device. It is disturbing that the large files transfer at a slower rate.
    • Would a RAID0 config get me faster write speeds than RAID1? I have another NAS that can do other RAID configs, which is fastest as far as write times?
    RAID0 (Striped) is generally faster, as the I/O is spread across 2 disks.
    RAID1 is mirrored, so you can not free the buffer until the same data is on BOTH disks. The disks are NOT going to be in rotational sync, so at least one of the disks will have to wait longer for the write sectors to move under the write heads.
    But RAID1 gives you redundency. RAID0 has not redundency. And you can NOT switch back and forth between the 2 without reformatting your disks, so if you choose RAID0, you do not get redundency unless you provide your own via a backup device for your NAS.
    • what is the most efficient transfer protocol? ftp? smb? something else? And am I better off invoking the protocol from the terminal, or is the overhead of an app-based client negligible?
    Test the different transfers using a large file (100's of MB or a GB sized file would be good as a test file).
    I've had good file transfers with AFP file sharing, but not knowing anything about your NAS, I do not know if it supports AFP, and if it does, whether it is a good implementation.
    If your NAS supports ssh, then I would try scp instead of ftp. scp is like using cp only it works over the network.
    If your NAS support rsync, that would be even better, as it has the ability to just copy files that are either NOT on the destination or update files which have changed, but leave the matching files alone.
    This would help in situations where you cannot copy everything all at once.
    But no matter what you choose, you should measure your performance so you choose something that is good enough.
    • If a client is fine, does anyone have a suggestion as to best one for speed? Doesn't have to be free -- I don't mind supporting good software.
    Again just test what you have.
    • Whats a good number to allow for simultaneous connections, given the number of files and their size?
    If the bottleneck is the NAS, then adding more I/O that will force the disk heads to move away from the current file being written will just slow things down.
    But try 2 connections and measure your performance. If it gets better, then maybe the NAS is not the bottleneck.
    • What question am I not asking?
    You should try using another system as a test destination device in the network setup to see if it gets better, worse, or the same throughput as the NAS. You need to see about changing things in your setup to isolate where the problem might be.
    Also do not rule out bad ethernet cables, so switch them out as well. For example, there was a time I tried to use Gigabit ethernet, but could only get 100BaseT. I even purchased a new gigabit switch, thinking the 1st was just not up to the task. It turned out I had a cheap ethernet cable that only had 4 wires instead of 8 and was not capable of gigabit speeds. An ethernet cable that has a broken wire or connector could exhibit similar performance issues.
    So change anything and everything in your setup, one item at a time and use the same test so you have a pear to pear comparision.

  • Jumbo frame ethernet

    I came across a number of articles relating to jumbo frame gigabit ethernet and integrating into existing networks with fastethernet and 1518 frame size gigabit ethernet devices. Heres a quote i'd like to discuss...
    "Today, however, applications optimized for large frame sizes can easily be integrated with existing Ethernet LANs without causing interoperability problems. For example, you can partition a logical network in which systems can exchange Jumbo Frames and mark them with IEEE 802.1Q virtual LAN tags. The extended frames will be transparent to the rest of the network.
    Adapters that implement IEEE 802.1Q can support different Ethernet frame sizes for different logical network interfaces. For example, a server could communicate with another server using Jumbo Frames while communicating with clients sitting on another VLAN or IP subnet using standard Ethernet frames - all via the same physical connection."
    The use of VLANs to ease interoperability issues is discussed in numerous articles and papers on jumbo ethernet - however, can someone pls explain why cisco have and the implications of the design decision they have taken with the 3750 switches to have no flexibility with configuring jumbo frame support, It can't be assigned on port-by-port basis, nor even on a VLAN basis but is set system wide so on a 24 port 10/100/1000 switch all ports are configured as jumbo regardless of what the connected client devices support.
    Are there any plans to upgrade the IOS to support configuring jumbo frames on per VLAN basis. Jumbo frames are an important issue to us as we can benefit from the performance increases and the improved server CPU utilization. Any thoughts ?

    Best practice here is to segment your Jumbo Frame servers on their own VLANs for Jumbo supported systems only.
    As a post here has already mentioned, Path MTU discovery will tell the systems on the Jumbo VLANs to keep the frames under 1500 when talking to a non-Jumbo VLAN.
    http://www.cisco.com/univercd/cc/td/doc/product/lan/cat2970/12225see/scg/swint.htm#wp1154596
    Please rate all helpful posts.
    Brad

  • [BUG] Jumbo frames issues after suspend/resume

    I have a 2.66Ghz MacBookPro5,1 which I recently upgraded to Snow Leopard. It's connected to a gigabit LAN and makes use of jumbo frames (MTU 9000).
    Everything was working flawlessly under Leopard, but since the upgrade to 10.6, I've noticed some very strange networking behavior. Essentially, networking goes AWOL as soon as it tries to transfer big data chunks *after a suspend/resume*. Remote sessions (ssh), file tranfers (ftp/afp) are affected.
    AFAICT, small packets work (eg, the output of "uptime" in a ssh session works just fine), but anything "big" (copying a large file over ftp or afp) hangs the connection. It seems that reducing the jumbo frame max size (using "ifconfig en0 mtu <whatever smaller than the previous setting>") temporarily fixes the issue, until the next hang.
    This problem only happens after suspend/resume. Upon cold boot, everything works just fine, so I'm suspecting a driver issue.
    The only difference between previously "working just fine" situation and the current issue is the upgrade from 10.5 to 10.6. I should mention I'm running in 64bit mode.
    HTH
    Message was edited by: thibaut

    If you have found a verified and reproducible bug then report it here: Feedback. The Discussions is not a bug reporting venue. Apple engineers do not read the Discussions.
    If you want help resolving a problem that is the purpose of the Discussions, but you need to post a question.

  • Jumbo frame support with BGP MSS size

    Hi All,
    I am working at small SP. we are going to enable Jumbo Frame support from end to end. Our core segment have MPLS cloud and packet size could be able support  up over 9000 already. Since our Core segment router  are running pure BGP with our edge/access segment router , when I enable jumbo frame support on their  interface level, I still can see BGP MSS size is 1260 right now. so my question, do I need  increase BGP MSS size between our core router  and edge router for transiting our SP cloud  traffic packet ?
    many thanks!
    Eric

    hi Harold,
    I have other question about MSS size for IPv4 and IPv6 BGP session, if the physical link MTU size is 1500 ( same as 1514 on ASR 9K platform), why IPv6 BGP MSS is 1240 and IPv6 BGP MSS is 1220? As I only understand IPv4 headr 20, tcp header 20, but didn't match these MSS size number, I am sure I mis-understand some value in between, could you please let me know how we get 1240 and 1220?
    many thanks!
    Eric

  • Which Macs Support Jumbo Frames?

    Is there a list anywhere of which Macs support Jumbo Frames and which don't? I can tell my Mac Pro does, and my MacBook does. But sadly, my G4 does not, even though it has gigabit ethernet. Unfortunately, the G4 is my home server so it's the computer that would benefit me the most by supporting them. Just going from my mac pro to macbook, my transfer speeds jumped from 40MB to 50MB/sec. And that may have been bottlenecked by the MacBook's hard drive.

    Hey l008com,
    Is true
    http://img38.imageshack.us/img38/6452/picture1rox.png
    How the heck do you embed an image in this forum?
    Add a ! between the link like this (I add the " " between it so you could see).
    "!http://img38.imageshack.us/img38/6452/picture1rox.png!"
    and with the " " removed ...
    !http://img38.imageshack.us/img38/6452/picture1rox.png!
    Anyway, GET IT NOW? 1504 is the limit, even though it's the built in gigabit ethernet on a dual 800 quicksilver G4.
    But anyhow now that I have more info about your G4, does it have a built-in 10/100/1000BASE-T Ethernet connector and four-port 10/100BASE-T Ethernet PCI card (RJ-45 connectors)? If I'm correct about this then the gigabit port is an Uplink Port for a Hub, a Switch, another Server, Access Point or some other Network Device. I know that's not much help but the more I know about about your existing Network Setup, the less I guess about it. One thing to keep in mind is that your ISP Internet Connection is slower that 10MB/s anyway plus the their MTU's are NOT the same size and I know why.
    But that really doesn't much if your Network Speed is more important than the Internet Speed.
    Later ...
    Buzz

Maybe you are looking for