I need to set up a local connection between my Windows 11 PC and an external device (IP 10.0.0.10), with jumbo frames enabled (MTU 9000). The end goal on my PC is to connect to the remote device from WSL2, which currently works but has the same MTU issues.
At the end of the post, I put the steps I followed to set the MTU.
However, I still cannot ping my device with a large packet size. The strange thing is that I get a default ping fail message, and not a packet too large ping fail message.
To compare, let me show you the result of a normal ping (#1), a ping with a packet too large (#2), and a ping with a packet that should be handled by the jumbo frame (#3).
# 1.
ME> ping 10.0.0.10
Envoi d’une requête 'Ping' 10.0.0.10 avec 32 octets de données :
Réponse de 10.0.0.10 : octets=32 temps<1ms TTL=64
# 2.
ME> ping 10.0.0.10 -f -l 10000
Envoi d’une requête 'Ping' 10.0.0.10 avec 10000 octets de données :
Le paquet doit être fragmenté mais paramétré DF.
# 3.
ME> ping 10.0.0.10 -f -l 8200
Envoi d’une requête 'Ping' 10.0.0.10 avec 8200 octets de données :
Délai d’attente de la demande dépassé.
Statistiques Ping pour 10.0.0.10:
Paquets : envoyés = 1, reçus = 0, perdus = 1 (perte 100%),
# 1.
~$ ping 10.0.0.10
PING 10.0.0.10 (10.0.0.10) 56(84) bytes of data.
64 bytes from 10.0.0.10: icmp_seq=2 ttl=64 time=1.49 ms
# 2.
~$ ping 10.0.0.10 -c 10 -M do -s 10000
PING 10.0.0.10 (10.0.0.10) 10000(10028) bytes of data.
ping: local error: message too long, mtu=9000
# 3.
~$ ping 10.0.0.10 -c 10 -M do -s 8900
PING 10.0.0.10 (10.0.0.10) 8900(8928) bytes of data.
--- 10.0.0.10 ping statistics ---
10 packets transmitted, 0 received, 100% packet loss, time 9368ms
To summarize, #1 returns a ping, #2 returns a packet too large error, and #3 returns a default error.
As you see, behavior #1 and #2 are normal, but not #3. The packet size is not too big to be handled by MTU (or else, I would have had the same error as #2).
I looked this problem up online and the answer I found was: my PC is configured correctly, but the receiving device does NOT have a MTU big enough. However, this device is specifically made to handle these large packets, I contacted the device's maker and they told me that it natively handles jumbo frames.
Where does this problem come from and what can I do to send large packets to 10.0.0.10 ?
The problem seems to be on my connection, but I can't find anything.
Steps followed to set MTU
- Powershell:
PS C:\Users\me> Set-NetAdapterAdvancedProperty "Ethernet*" -DisplayName "Jumbo Packet" -RegistryValue "9014"
PS C:\Users\me> Get-NetAdapterAdvancedProperty
Name DisplayName DisplayValue RegistryKeyword RegistryValue
---- ----------- ------------ --------------- -------------
(...)
Ethernet 4 Jumbo Packet 9014 Bytes *JumboPacket {9014}
(...)
- Command line:
netsh interface ipv4 set subinterface "Ethernet 4" mtu=9000 store=persistent
netsh interface ipv4 show subinterfaces
MTU État détect supp Octet entrant Octet sortant Interface
---------- --------------- ------------ ------------ -------------
(...)
9000 5 0 0 Ethernet 4 - Adaptateur TPL Blanc
(...)
ncpa.cpl (Network administration tool):
- Ethernet 4 --> configure --> advanced --> Jumbo Packets --> 9000
- WSL:
~$ sudo ifconfig eth0 mtu 9000 up
~$ ifconfig
eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 9000
inet 10.0.0.3 netmask 255.255.255.0 broadcast 10.0.0.255
inet6 fe80::215:5dff:fe8a:1792 prefixlen 64 scopeid 0x20<link>
ether 00:15:5d:8a:17:92 txqueuelen 1000 (Ethernet)
RX packets 74 bytes 12574 (12.5 KB)
RX errors 0 dropped 3 overruns 0 frame 0
TX packets 34 bytes 92254 (92.2 KB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
