MX80 performance issue

[SF0204]

Hi, 

My company use MX80 as outbound firewall + router. We have 2 Wan internet direct connected to Internet & Lan2 port.

If i enable PPPOE on Lan2 as second Wan, then all system seems slow down: bandwidth while copying between local vlans down to <300kB/s, Internet download and upload ~ 300kB/s (with whitelist client). SpeedTest : download ~6Mbps, upload ~6Mbps

But, if i disable PPOE on Lan 2 as well disable Lan 2 port, everything works well, Donwload adn upload speed on speedtest up to 70 ~ 80mbps, copying speed between intervlans upto 10MB/s.

Can someone help me?

Thanks.

[PhilipDAth]

Have you configured it to use WAN2 (such as with load balancing) or only for failover?

If it is doing load balancing, perhaps the second ISP isn't that fast ...

[SF0204]

Hi, it's configured only for failover . Both of pppoe connections have bandwith = 80Mbps.

[PhilipDAth]

I don't know the answer, but I wonder if this is something to do with using circuits with different MTUs.  The MX80 is getting a little long in the tooth now ...

You can't configure the MTU yourself.  You could open a support case and ask support to lower the MTU on WAN1 to match the value being used by WAN2.

I just thought how you could test this yourself first.  On your workstation lower the MTU to something like 1400.  Does this then resolve the issue?  If it does get support to adjust the MTU, otherwise it is a different issue.

[SF0204]

Hi Philip, thanks for your suggest, i will test by change MTU size by another router manufacture. It's very complicated case, i even haven't any idea for this.