"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]
146 questions
2
votes
1 answer
Telecom provider not supporting MTU higher than 1515 for leased line
We have ordered a 100 Mbps leased line and did not specify our requirement to have a minimum of 1530 MTU supported. The telco now sent us a feedback that they do not support 1530, but only 1515.
Did anyone experience something similar? And what can…
Paul Moe
1
vote
0 answers
MTU 9000 and 1500 when machines with MTU 1500 send data to machines with MTU 9000
we have some machines in the cluster
linux machines as Linux_a , linux_b are configured with MTU 1500
while linux machines - linux_1 and linux_2 are configured with MTU 9000
so
linux machines - linux_a and linux_b send heavy data to linux_1 and…
![](../../users/profiles/423473.webp)
shalom
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1
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2 answers
can we mix MTU values in cluster
we have hadoop cluster ( all machines are linux redhat machines version 7.x )
on the VM machines we set MTU=8900 and all other machines we set MTU=9000
we set on VM MTU=8900 because we saw some network problems with MTU=9000
My question:
dose mix…
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shalom
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1
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1 answer
Problems with TCP retransmission, duplicates etc. on CentOS Linux
I'm running Vyattagateway with a CentOS Linux behind, and IPSec tunnel in front.
Trying to display my setup:
PARTNER-NETWORK <--- IPSec (GRE, MTU 1420) ---> VYATTA (TUNNEL, MTU 1420 <> eth0, MTU 1500) <---> CentOS (eth0, MTU 1500) <---> internet…
![](../../users/profiles/462832.webp)
Alfred Balle
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2 answers
how to know if my servers should use huge pages ( memory page size )
we have several servers in cluster , and we want to know what in general in which cases we need to configure huge pages ?
I have also few quastions
dose "memory page size" is equal to Huge pages ?
in my linux server I entered the following command…
![](../../users/profiles/423473.webp)
shalom
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1
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1 answer
Random connection resets between browser and Linux server - MTU wrong or ICMP not getting through?
I've been seeing random ERR_CONNECTION_RESET errors in my browser (Chrome, Firefox or Edge running on different machines, Windows 10 1709) when I try to edit web pages on a remote Linux server running Ubuntu 16.04 LAMP. It's very hard to pinpoint…
![](../../users/profiles/265033.webp)
Phil McKerracher
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1
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1 answer
VLAN MTU on Linux with Intel Pro/1000 PT Server Adapter
For some reason MTU still seem to be an occasional issue with trunked connections.
In this case I have a trunk connected to an Enterprise Linux 5 server. I use standard vlan seperation in Linux, and have the vlan interface bridged with virtual…
![](../../users/profiles/22153.webp)
Roy
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3 answers
ping fails with MTU >= 298
For context, my original problem is that my ssh connection to my servers hangs at expecting SSH2_MSG_KEX_ECDH_REPLY when i connect to them via VPN (in this case, an OpenVPN running in pfsense).
The Internet indicates that may be linked to MTU…
![](../../users/profiles/350398.webp)
iCart
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0 answers
VirtualBox adapter MTU settings over 1500
I create an adapter for Oracle VirtualBox (as a host-only). It runs perfectly; but I need to change MTU size to 1600. When I come back to host-PC and I opened terminal. Then I got these results.
ifconfig :
.....
vboxnet0 Link encap:Ethernet HWaddr…
![](../../users/profiles/428688.webp)
user428688
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- 2
1
vote
2 answers
Is there a utility or way to get the PMTU/MTU of a remote system quickly?
Is there a utility or linux built in to get the PMTU/MTU of a remote system quickly (sub 1 second preferably)? If so what is it and what syntax does it require?
Google searches have not been my friend today and the only solution I've found is a full…
![](../../users/profiles/194966.webp)
Bravo Delta
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1 answer
Jumbo frames (mtu 9000) on Debian 7.10 servers with BCM57800 NIC (bnx2x)
I'm working on 2 servers under Debian 7.10 with Broadcom Corporation NetXtreme BCM57800 1/10 Gigabit ethernet.
I have done the following for both servers:
ethtool -g eth0
Ring parameters for eth0:
Pre-set maximums:
RX: 4078
RX Mini:…
![](../../users/profiles/366400.webp)
Eliot B.
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1
vote
0 answers
VLANs with mixed MTUs trunked over a LAG
I'm contemplating enabling Jumbo frames for a specific network/VLAN (a dedicated storage network). Ports are spread across two switches, linked together using a LAG, which is configured to carry all relevant VLANs (trunking).
I presume the…
![](../../users/profiles/250029.webp)
sxc731
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1 answer
Linux MTU and UDP
Can someone please explain this behavior to me? I have a few VMS (centos) running on a cloud provider. The interface is set to the standard 1500 MTU.
pinging with large ICMP packets works fine:
# ping -s 1600 10.132.6.3
PING 10.132.6.3…
![](../../users/profiles/304163.webp)
Dave0
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2 answers
Weird network interaction between Vista and Ubuntu
I have a network where my WAN (a CableModem) goes into a (dubiously configured) Ubuntu box which acts as the router for the whole company.
We recently switched our ISP, and we're getting a very weird behavior. In Vista/Server 2008 machines, some…
![](../../users/profiles/1168.webp)
Daniel Magliola
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1
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1 answer
VPN problems: MTU and Don't-Fragment
I am setting up a VPN on Ubuntu 14.04LTS which uses IPSEC and performs NAT for clients. It is basically working - I can connect to it from a clinet (Android device) and browse (for example) www.google.com.
However I cannot browse www.bbc.co.uk. …
![](../../users/profiles/288821.webp)
Mark Smith
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