"Maximum Transmission Unit" (MTU) is the maximum number of bytes a frame or packet may have on a network (in several layers of the OSI model). Wrong MTU can lead to packet loss.
Questions tagged [mtu]
155 questions
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Different length between ping and tcpdump
I do not why I am not able to see under tcpdump the correct length value which should be $((9706-28)) = 9678, but I see 9686. On both side there is a MTU set to 9706 which maximum value for the interface which I am using.
I run command:
ping -D -s…
sqr
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Requirements to achieve Jumbo Frame (mtu = 9000) with PXE Enabled networks
What I should be looking for when trying to enable Jumbo Frames in networks that relies on PXE for server booting?
As far as I know I must have:
Network switch capable of MTU >= 9000
The ability to enable Jumbo Frames not only on the network…
Vinícius Ferrão
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SSH pauses - perhaps MTU/packet size too large - how to confirm and possibly resolve?
I have a MacOS client and Linux server (non-root access). I'm using 2 versions of a tool for remote desktop control. Version 2 worked pretty well - some small bugs. The vendor has updated to version 3. Version 3 fixes many bugs but has one major bug…
nachum
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Does changing MTU need restarting the application?
Let us say we have an aerospike cluster running with interface mtu as 1500. If I want to switch to jumbo frames, do I need to restart the aerospike cluster? If yes, why?
Tarun Dev
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hetzner private network, 1 docker host, 1 pfsense, I keep getting "TCP Previous segment not captured" from my containers
this is the network design
https://imagebin.ca/v/5NNDpuDwq9PT
it's hosted on hetzner, 1 firewall with a public facing interface, pfsense.
1 docker host with two interfaces, one connected to the private network and one facing the internet, the public…
dada216
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how to safely increase a network's MTU
I want to increase the Ethernet Maximum Transmission Unit (MTU) for some hosts on a local network. Is there a known sequence of steps to follow? Or, can I just tweak each host's MTU as needed and it will "just work"?
One condition is only some…
JamesThomasMoon
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Path MTU is not always 9000, only in one direction
I have a question about MTU or path MTU. In my setup I have 2 computers (firewall, Windows PC) and one NAS, each with a gigabit interface. They are connected throughout the same gigabit switch. In all of them I configured a MTU of 9000. Also…
Hirsch
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How is the Ethernet payload only max 1500, while I can ping with larger size packet?
Just recently I came to know that the payload of Ethernet is max 1500 bytes (mtu).
The first thing that came to my mind was that we can ping with much more size than that. So I thought maybe the ping packet is being fragemented in someway. So I…
AhmedWas
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Ping : How to differentiate between Host powered off and MTU too long?
I changed the eth0 MTU size to 1550(using : ifconfig eth0 mtu 1550) and ran ping -c 1 -M do -s 1500 -w 5 {some other IP} and
The output I see is,
--- x.x.x.x ping statistics --- 5 packets transmitted, 0 received, 100% packet loss, time 4001ms
The…
PleaseHelp
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Force jumbo packet fragmentation
We are in a cluster environment. We have compute nodes with jumbo packets enabled and a MTU of 9000. We are running into some issues in tracebacks to an address outside of our lan, where jumbo packets are being dropped due a firewall with a standard…
Martin Forde
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dose setting Jumbo frame on linux redhat influencing OS performance?
We set the MTU to 9000 on all our linux machines ( we have redhat machines version - 7.3 ) , linux machines are part of hadoop clusters
we want to know if set the MTU to 9000 can be negative on OS performance?
Dose set other Jumbo frame value as…
shalom
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linux fine tuning after setting the MTU to jumbo frame
We want to set the MTU to 9000 bytes on our Linux machines (distribution is Redhat 7)
In this case, how would I tune the memory page size according to MTU size of 9000 bytes?
Also, what are the risks associated with setting the MTU to 9000 Bytes?…
shalom
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MTU issue - Packet loss with certain Destination
A customer is having issue with our system and after investigating and analyzing tcp traffic with tcpdump, I noticed that fragmented packets were not received by our cloud server (OVH).
I did some tests:
Changed the cloud server address to our old…
JPelletier
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Centos 7 pptpd mtu size
i'm using pptpd on centos7 as PPTP VPN Server
how can I change the MTU size on server side cause some users cannot connect to the server
thanks
Pedram Masoumi
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Cisco 2960X and Jumbo frames on particular ports
I would like to setup several ports to be able handle jumbo frames.
This will be only for my backup nas connected to ESXi host.
I did create vlan 103 where I changed mtu size to 9000.
Problem is when I want to check accpetation of jumbo frames…
Roman Bielich
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