Hello,
I just got my first MT device, a RB2011UiAS-2HnD-IN and am very eager to learn to use it’s myriad features. I used it to replace my current Asus RTN12 which is connected to a TP-Link ADSL modem. This is used at home.
I used the quickset option to set it up as a Home AP. Apart from configuring Wi-Fi, PPPoE and IP Accounting, I have not made any other changes AFAIK.
I have problems while broswing some web sites only. There are three types of issues now, maybe due to same root cause (?):
- Some web sites do not load at all. Example speedtest.net. The browser keeps “spinning” but nothing happens, no error messages either.
- Some web sites load slowly (images take quite some time to load). Sometime images wont load, but a browser “refresh” will make them crawl in.
- Some web sites do not seem to finish loading (even though the page appears to be fully loaded, the browser keeps “spinning”).
I know some networking basics, but definitely am not an expert. I tried to rule out DNS, by directly configuring my PC with 192.168.88.1, OpenDNS, Google 8.8.8.8, etc (at different times) but it made no improvement.
I would be grateful for your help in resolving this issue.
Can you repeat the same issues on the same sites ? Do you get stable ping from e.g. speedtest.net ?
/ping [:resolve speedtest.net]
Please check the log file, is there some disconnection or linking records?
I’m at work now, so I’ll check for consistent pings this evening when I get back home.
1st issue is 100% consistent on speedtest site. The other two issues are observed some times and not always. Issue is seen even if I use different browsers. Issue is never seen if I disconnect my RB2011 and reconnect my older Asus router to the modem.
I did not see any messages appear in the log window on BoxWin when I was having these browsing issues. Is there additional debug logs or similar than can be turned on?
Also it would be good if you could send us the supout file from your device, so we could check your router configuration and see the cause of this issue.
http://wiki.mikrotik.com/wiki/Manual:Support_Output_File
Email:
support@mikrotik.com
You mention PPPoE, so the first thing that I would look at is your MTU. Verify that it’s 1492, as PPPoE takes 8 bytes off of the standard 1500.
PaulsMT, I have emailed my rif file to support@mikrotik.com. I can also confirm now that pinging speedtest.net gives consistent 275 msec ping (+/- 5 msec variance) with no packet loss. Just now discovered another site fortune.com which also never loads for me (beyond a change in the browser tab title).
IntrusDave, I checked the “pppoe-out1” interface window and saw the “Status” tab shows MTU=1460 and MRU=1480. I changed the MTU from 1480 to 1460 in the “General” tab of the same window, which caused the PPPoE link to drop and connect again. Unfortunately this has not helped improve the situation.
Anything else I need to check, please do let me know.
You need to find your optimum MTU Value for your provider. Follow below instructions to find your optimum value and change accordingly.
General instruction for finding your optimal MTU size
Go to Start and select Run.
Set router to MTU 1500 to start with.
Start RUN
Type in cmd (Windows 2000/XP/Vista/7) or
command (Windows 98/ME) into the box .
Hit the enter key or click OK
At the DOS prompt,
type in ping bbc.co.uk -f -l 1492 ( *or your choice of site)
and hit the Enter key.
If you get the response “Packet needs to be fragmented but DF set”,
lower the size the packet in increments of +/-10 (e.g. 1472, 1462, 1440, 1400)
until you have a packet size that does not fragment.
Now increase the packet size from this number in small increments until you
find the largest size that does not fragment.
Add 28 to that number (IP/ICMP headers) to get the optimal MTU setting.
For example, if the largest packet size from ping tests is 1462, add 28 to 1462
to get a total of 1490 which is the optimal MTU setting and can be put
in your router’s settings
!
Hope this helps some of you !
In your PPP profile used by your PPPoE client, enable Change TCP MSS. It should solve reachability of some sites..
imagica & Muqatil, thanks I tried playing around with MTU and MRU values set in the General tab of the PPPoE connection window. I found that decreasing these numbers was allowing previously unloadable sites to load in the browser, but the ping and ul/dl bandwidth was terrible. Finally settles on MTU and MRU number quite a bit lower than what the PPPoE Status tab was showing (almost 40 down, don’t recall exactly as I’m currently away from the router), and I also had to reduce the MRRU (I know, it’s for MLPPP and should not matter to me, but I was trying quite a few things to make it all work). Tonight I will revert back MRRU and ensure it’s still fine.
BTW, I did set “Change TCP MSS” to “no” but it didn’t help. I did see that there were 2 firewal mangle rules for reducing MTU on both inbound and outbound interfaces, and these were changing MSS to the MTU and MRU value minus 20 than (the values reported in the PPPoE Status tab), whenever the MSS was exceeding the MTU and MRU. When I set my own lesser values in the PPPoE General tab, those were used instead, and ended up working fine.
I’m just a bit surprised that a working MTU for me is so much lower than 1490. Anyway all’s well that ends well and happy that it got me started on the Mikrotik path of enlightenment. Thank you all for your support.
Hi,
Also try disabling MRRU then playing with the MTU, MRU settings again. I’ve come across a few PPPoE connections where having it enabled caused havoc or the connection just didn’t plain work, the second I disabled it and restarted the PPPoE session things just fell into place.
It may not work for you but I’ve found that various BT OpenReach equipment just doesn’t play well with it, regardless of the values you pop in it.
Are you still using that tp-link as DSL modem? Guess it setup as a bridge, have you checked MTU there??