Enable jumbo frame on 192.168.1.1

[bigeyes0x0]

I'm using AC56U with latest 380.59 merlin firmware and during optimizing for the NAS on the router I found out that interface br0 with router IP only has mtu 1500 even if I have jumbo frame enabled in switch control and made sure that any intermediate switch between my device and the router has jumbo frame enabled. I have 2 switches between my tested device and the router with complicated VLAN setup for my usage with IPTV but I have tested and made sure that ping -f -l 8950 <other device> have worked regardless if <other device> connected to router, switch 1 or switch 2.

I tried to fix this on the router using these commands

ip link set eth2 mtu 9000 # in br0
ip link set eth1 mtu 9000 # in br0
ip link set eth0 mtu 9000 # in vlan1
ip link set vlan1 mtu 9000 # in br0
ip link set br0 mtu 9000

Some of these commands cause disconnection on my ssh or https session to my router and after the final command on br0, accessing web ui is impossible, but ssh still works. I checked with command ip a and these mtus do stick. Still checking jumbo frame with ping -f -l 8950 192.168.1.1 does not work, and it simply returns timeout.

Any idea?

 

[bigeyes0x0]

Bump.

 

[slidermike]

big, I dont have the Asus router you have but I do know a similar discussion came up about a year ago on the dd-wrt forums for the Netgear R7000 router.
In the end, the router WAN interface hardware had a phy limit where as the LAN switch might have supported jumbo frames.

So what I am suggesting is that you google the hardware specific to your router and see if in any of the FCC filings or other publicly available resources it is explained what the hardware is capable of.

Good luck

 

[mstombs]

Does your router firmware version have the Broadcom switch control tool "robocfg"? Would have throught the web gui config would use this, but login via shh and see what it can do for you, i.e.

robocfg showports
Switch: enabled gigabit
Port 0: 1000FD enabled stp: none vlan: 2 jumbo: off mac: 00:01:5c:.
Port 1:  100FD enabled stp: none vlan: 1 jumbo: off mac: 00:12:17:.
Port 2: 1000FD enabled stp: none vlan: 1 jumbo: off mac: 58:94:6b:.
Port 3:   DOWN enabled stp: none vlan: 1 jumbo: off mac: 00:00:00:00:00:00
Port 4: 1000FD enabled stp: none vlan: 1 jumbo: off mac: 00:11:0a:.
Port 8: 1000FD enabled stp: none vlan: 1 jumbo: off mac: 08:60:6e:.

 

[thiggins]

Do you find that using jumbo frames really makes a difference in throughput? Today's NICs and drivers usually work as well or better without jumbo frames.

 

[bigeyes0x0]

Just try it out as it did make a difference for my own built NAS using a SBC here http://www.hardkernel.com/main/products/prdt_info.php?g_code=G143452239825. From all the information you guys provided I guess it's not possible with my router (supposedly this is the same platform as the R7000) and not really does much for it in theory anyway considering it's a network device which should have supported stuffs that made Jumbo frame obsolete anyway. The reason it made a difference for that SBC is likely because it uses a USB based Ethernet chip.

 

[RMerlin]

Do you find that using jumbo frames really makes a difference in throughput? Today's NICs and drivers usually work as well or better without jumbo frames.

A few years back, I did some tests, and I barely saw any difference in SMB throughput. Since I got a NAS, my SMB throughput already saturates my Gigabit Ethernet, so I feel that the headache associated in getting everything configured to use the same frame size isn't worth the very minimal benefit. As you mention, today's NIC efficiency and CPU power make jumbo frame add very little to the equation.

 

[Elbowman]

Hello.
Worth or not applying, may I ask you for support?
I have set through GUI Jumbo Frame to enabled, adjusted NIC on both test laptops to 9k JF also.
Pinged target with following result

> ping -f -l 8973 xxx.xxx.xxx.xxx

Pinging xxx.xxx.xxx.xxx with 8973 bytes of data:
Packet needs to be fragmented but DF set.
Packet needs to be fragmented but DF set.
Packet needs to be fragmented but DF set.
Packet needs to be fragmented but DF set.

Ping statistics for xxx.xxx.xxx.xxx:
Packets: Sent = 4, Received = 0, Lost = 4 (100% loss),

There's no problem with packet length of 8972.

Do you have any idea, what's the problem?