Bug #1964
closed
Changing MTU on pfSense 2.0 doesn't work
Added by Alessandro Bolletta almost 14 years ago.
Updated almost 14 years ago.
Affected Architecture:
All
Description
I tried to change MTU on pfSense 2.0 into 1496 because of my internet connection needs. While i could get it working flawlessly in pfSense 1.2.3, on pfSense 2.0 (even in beta and RC, now also in final version) i can't get MTU working. I tried to install it in a virtual machine over KVM hypervisor, over Hyper-V, also bare-metal , i tried with every model of ethernet card, i tried to rebbot after every change, i tried every possible value on MTU and MSS box (but I think that typing 1496 on MTU and MSS box is correct) and I couldn't get it working. If I do an "ifconfig" in the shell, it shows correcty the MTU value on the interested network card.
I tried to ask help in the forum but nobody couldn't help me.
I assigned an urgent priority because I think that this bug is very serious.
- Status changed from New to Rejected
- Priority changed from Urgent to Normal
Please keep the discussion on the forum until a bug is confirmed. Changing the MTU works fine.
[2.0-RELEASE][root@pfSense.localdomain]/root(1): ifconfig em1
em1: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
options=9b<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,VLAN_HWCSUM>
ether 00:0c:29:41:01:67
inet6 fe80::20c:29ff:fe41:167%em1 prefixlen 64 scopeid 0x2
inet 192.168.1.1 netmask 0xffffff00 broadcast 192.168.1.255
nd6 options=3<PERFORMNUD,ACCEPT_RTADV>
media: Ethernet autoselect (1000baseT <full-duplex>)
status: active
(Changed it to 1450 in the GUI, then...)
[2.0-RELEASE][root@pfSense.localdomain]/root(2): ifconfig em1
em1: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1450
options=9b<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,VLAN_HWCSUM>
ether 00:0c:29:41:01:67
inet6 fe80::20c:29ff:fe41:167%em1 prefixlen 64 scopeid 0x2
inet 192.168.1.1 netmask 0xffffff00 broadcast 192.168.1.255
nd6 options=3<PERFORMNUD,ACCEPT_RTADV>
media: Ethernet autoselect (1000baseT <full-duplex>)
status: active
MTU changed fine.
Yes, I get the same ifconfig when I change MTU on the WebGUI, but it doesn't work, while if I do the same things in pfSense 1.2.3 or in Kerio Control firewall it works as it should. Why?
Here's my ifconfig after MTU change.
[2.0-RELEASE][root@pfSense.localdomain]/root(2): ifconfig em2
em1: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1496
options=9b<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,VLAN_HWCSUM>
ether 00:0f:35:21:10:36
inet6 fe80::20f:eaff:fe91:407%em1 prefixlen 64 scopeid 0x2
inet 192.168.10.1 netmask 0xffffff00 broadcast 192.168.10.255
nd6 options=3<PERFORMNUD,ACCEPT_RTADV>
media: Ethernet autoselect (1000baseT <full-duplex>)
status: active
Then your MTU is 1496. It changed as it was supposed to - which means the MTU change is not the problem, and you have something else going on. All the more reason to keep discussing it on the forum.
Why in pfsense 1.2.3 or in a linux-based firewall as Kerio Control it works and in pfSense 2.0 it doesn't work???
I'm SURE that i made no configuration mistakes.
The ticket system is not for troubleshooting or help - please keep it on the forum.
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