EdgeRouter X / MWeb not able to reach certain sites

[GavAt]

Hi

This week I converted ADSL to Fibre with MWeb. I chose to use my own router, EdgeRouter X. I can access many sites and line speed tests are close to max (10 Mbps). The issue I am experiencing is I am unable to reach a number of sites. Examplesare ui.com, MWeb's browser email site (email.mweb.co.za), plus others. Also, Outlook times out connecting to the MWeb mail server. I have arranged a temporary ADSL connection while I resolve the fibre connection issue. If I connect PC to ADSL I am able to reach all these sites.

MWeb's technical support say the issue is with the EdgeRouter's configuration.

Doing some online research I cam across someone with a similar issue.
https://samuel.kadolph.com/2015/02/mtu-and-tcp-mss-when-using-pppoe-2/

Has anyone experienced a similar issue?

Best regards

 

[WAslayer]

The issue the article describes makes sense and you should start verifying that your router is configured to use the correct MTU and tcp MSS..

This is dependent on the specific devices your connection will interact with in reaching a destination, but all devices *should* honour the default MTU of 1500..

 

[Mal1ce]

You can clamp the MSS value from the Wizards tab under the ER-X web interface if using a more recent firmware (older versions had to be done via CLI).

I clamp to 1452 for PPPoE only, then set MTU to 1492 under the PPPoE interface on the Dashboard tab.


Had to do this for some GPON fibre networks (Openserve & Link Africa).

 

[GavAt]

You can clamp the MSS value from the Wizards tab under the ER-X web interface if using a more recent firmware (older versions had to be done via CLI).

I clamp to 1452 for PPPoE only, then set MTU to 1492 under the PPPoE interface on the Dashboard tab.

Had to do this for some GPON fibre networks (Openserve & Link Africa).

Thanks for the prompt response. I managed to download latested firmware via ADSL and then update the router. The Wizards are unavailable as I made changes to the config.

I don't know CLI commands but some searching of CLI command(s) identified the following comands to clamp to 1452 for PPPoE only.

set firewall options mss-clamp interface-type pppoe
set firewall options mss-clamp mss 1452

I changed pppoe interface MTU to 1492. Then I logged into CLI. Change to configure mode. Entered the above two commands, the did a committe and then save. There doesn't appear to be an improvement.

Dashboard show pppoe inteface MTU is 1492. How do I check the pppoe interface mss clamp value?

 

[Mal1ce]

Login to the ER-X via SSH.

Type "configure"

Type "show firewall options"

 

[jasweb]

On my Mikrotik I had to set the PPPoE Profile to default-encryption..

Think you have to set it to Encryption (not sure how to do it in the edgerouter).

Good luck!

 

[GavAt]

Login to the ER-X via SSH.

Type "configure"

Type "show firewall options"

Thanks. I checked and nss-clamp is set to 1452 but no improvement. I will search if there are other MTU and MSS-Clamp value sets.

 

[GavAt]

On my Mikrotik I had to set the PPPoE Profile to default-encryption..

Think you have to set it to Encryption (not sure how to do it in the edgerouter).

Good luck!

Thanks. I looked browsed thru the Config Tree but couldn't find such a config. I will search online.

 

[GavAt]

An update. MWeb technical department sent me a loan Zyxel router. Set it up this morning and I get the same problem, can't access many website due to timeout. However, the number of website I can't access is far greater and are the ones most of us rely on; google, youtube, netflix, fnb. Issue logged with their technical department. Spent a couple of hours on the phone today doing the basic checks; change DNS to Google, change MTU, etc. No improvement.

Connected PC to ONT Ethernet port and was able to connect to all those sites.

I have emailed the technician links to articles about MTU and MSS Clamping. The issue has been escalated to their seniot technical team. I hope they can resolve soon.