RT-AC66U - Slow WAN to LAN

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HavocRo

New Around Here
You are right, the cable that i plug into my PC it's the one coming from my ISP and there were no problems.
I also changed the cable between the router and my pc and there was no change.I tried more of your fws but the best until now it's the latest original Asus fw 979 with 280 Mbps DL.I discovered that I can execute that telnet command from within your fw and it showed 0.
I'm very disappointed as i had great expectations from it considering also the price of 200 Euro. :(
If you get any info that could help me it would be much appreciated.

p.s:I heard that ASUS has some beta FW in tests that should solve the PPPOE issue, do you know anything about it?Would it be good also for my problem?
 

RMerlin

Asuswrt-Merlin dev
You are right, the cable that i plug into my PC it's the one coming from my ISP and there were no problems.
I also changed the cable between the router and my pc and there was no change.I tried more of your fws but the best until now it's the latest original Asus fw 979 with 280 Mbps DL.I discovered that I can execute that telnet command from within your fw and it showed 0.
I'm very disappointed as i had great expectations from it considering also the price of 200 Euro. :(
If you get any info that could help me it would be much appreciated.

p.s:I heard that ASUS has some beta FW in tests that should solve the PPPOE issue, do you know anything about it?Would it be good also for my problem?
I'm not aware of any PPPoE-related fix. The beta that I have myself is for the RT-AC68U, and is intended to address issues with the 2.4 GHz band. I haven't heard any news about RT-AC66U development these past few weeks as they are busy finishing debugging the RT-AC68U. Where did you hear that?
 

HavocRo

New Around Here
I read it on some forums, tbh i don't remember which but the number of the fw was: 3.0.0.4.374.1631
Edit: I just received from Asus the beta above mentioned to test it with my router, fingers crossed
Update:It's useless, no change for Wan - Lan behaviour.
 
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Eokazan

New Around Here
I have same problem, ISP (Rostelekom) FTTB PPPoE direct cable (4wire cable) to PC Lan 65Mbps, through router 26-30Mbps. HW acc enabled.
Tried to flash 3.0.0.4.354 Beta - no change.
Tonight I try to test with my old Trendnet TEW-672GR - it's ok.
 
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Symbiot

Regular Contributor
same issue but not running pppoe, just running automatic IP.
anyone have a link for merlins 354 fw?
 

Symbiot

Regular Contributor
Has anyone found a fix for the slow wan speed?

I tried merlin .246 and I saw the same issue.

when flashing I did:

Flash firmware without WAN cable.
clear nvram.
Factory reset
configured
tested
same difference.

When I plug into my fiberchannel router directly I am seeing 4-500mbps / 7-800mbps
when plugging asus into fiberchannel router and laptop into asus I see 1-200(max) / 1-200(max)

What gives?
 

prelude

Occasional Visitor
Has anyone come up with a solution for this? I'd like to get this working, finally.

If no solution has been found, would an upgrade to AC68U do the trick?
 

Barista

New Around Here
Hi all,

I'm having a similar issue with my VDSL connection.

The modem is a Sagemcom FAST 2864 with TekSavvy atm.

When I run directly off the Sagemcom I get 49.8Mbps/9.79Mbps, I am paying for 50/10. When I use my ASUS RT N65U running either Latest ASUS firmware or the Padavan N56U project ver. 3.0.3.8-081 I get 31.2/7.8 on average.

I have tried turning HW Acceleration on and off with no difference.

Any help would be appreciated.

P.S. On that note, is there a way i can have the modem handle PPPoE with the ASUS router handling everything else? Because that may solve the problem.

UPDATE/POSSIBLE SOL:Apparently it's not the ASUS router. The Sagemcom 2864 has a bug in its firmware that causes it to drop the speed of a connection when in PPPoE passthrough, the drop is relative to the speed of the connection. Bell confirmed this with TekSavvy but would not say anything about a solution. AKA they're not planning on addressing it. Go figure.

Anyways, I'm getting a SmartRG 505N in a few days, should help.
 
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spinach

Occasional Visitor
Sorry to resurrect this thread but I'm running into the same issue as Barista. I'm also on TekSavvy VDSL, paying for 25/10. I have a SmartRG 505N modem with the latest firmware. When I connect directly to it, I get 25/10 through Speedtest.

When I put it into bridge mode, then connect through my Asus AC66U running Merlin's firmware, my speed drops to 10/0.6.

Has anyone been able to sort this out?
 

spinach

Occasional Visitor
Bah, I figured out I had the QoS settings on my router configured for my old ISP service. Turned that off and I've got full speeds again.
 

Mihai Georgescu

New Around Here
I have a Asus RT-AC66U and Gigabit connection through PPPOE at some point it worked really good. After updating to the latest firmware i am unable to go over 100mb with my lan or Wifi connection.
If i plug the cable directly from the ISP to my Mac i have 910 MB/s download. If i test it through the router then i have around 90 MB/s same speed on Wifi and Cable. I have the hardware acceleration enabled. I don't really know what to check or modify to make it work back again.

I tested it with Asus FW_RT_AC66U_90043802695 and also with FW_RT_AC66U_30043789533.
I also tried with Merlin FW RT-AC66U_380.58_0.
 

justheretotellyouthis

New Around Here
Hi guys, I think I may be able to provide some clues to this issue (I'm a novice user however so this entire post may be totally off the mark).

I'm sitting on a 250/100 fiberoptics line. After setting up my RT-AC66U for the first time I was disappointed by the speeds I was getting (something like 130/40). My old router could actually push 245/80. So I installed the latest FW from Asus webpage, hoping it would solve the issue. It did not, still 130/40. I decided to restore to factory settings. The FW version did not reset (I may be wrong in assuming that it would), I still had the latest, but NOW I was getting full speeds.

Dissatisfied with other aspects, I decided to install Merlin (for some reason I had to install it during recovery mode). I was once more disappointed by the speeds I was getting (130/50), and I ended up here. Unable to find a solution however, I decided to restore factory settings once more. This time too, the firmware did not reset, so Merlin is still installed. And just like last time, I now get full speeds.

For some reason, it seems I have to to a factory reset after installing new FW to be able to get full speed. Can't explain it.
 

L&LD

Part of the Furniture
Hi guys, I think I may be able to provide some clues to this issue (I'm a novice user however so this entire post may be totally off the mark).

I'm sitting on a 250/100 fiberoptics line. After setting up my RT-AC66U for the first time I was disappointed by the speeds I was getting (something like 130/40). My old router could actually push 245/80. So I installed the latest FW from Asus webpage, hoping it would solve the issue. It did not, still 130/40. I decided to restore to factory settings. The FW version did not reset (I may be wrong in assuming that it would), I still had the latest, but NOW I was getting full speeds.

Dissatisfied with other aspects, I decided to install Merlin (for some reason I had to install it during recovery mode). I was once more disappointed by the speeds I was getting (130/50), and I ended up here. Unable to find a solution however, I decided to restore factory settings once more. This time too, the firmware did not reset, so Merlin is still installed. And just like last time, I now get full speeds.

For some reason, it seems I have to to a factory reset after installing new FW to be able to get full speed. Can't explain it.
You're seeing things work exactly as they are supposed to. :)

A reset to factory defaults does not magically flash back the firmware the router originally shipped with (you have to 'always' flash the firmware version you want installed). All it does is clear all the settings and previous customizations carried over from the last firmware on the router. This (now) gives the new firmware the best chance to work as designed, glitch-free. ;)

To fully 'sanitize' a network:
  • Perform a full reset to factory defaults and then minimally and manually configure the router to secure it and connect to your ISP. (As you have found out).
  • After doing the above, some users have found it necessary to actually flash (again) the firmware already installed for it to work properly. Then once again manually and minimally configure the router to secure it and connect to your ISP.
  • A few users have found that even with the above, clearing the NVRAM is also needed, followed once again by a minimal and manual configuration of the router.
  • I have had at least a couple of customers that also needed to use the 'Format JFFS partition at next boot' option and reboot (via the gui) the router at least 3 times while waiting at least 5 minutes between reboots too to have the router full 'clean' from any previous configurations and/or JFFS partition (or file) corruption.
  • Use new ssid's for all bands (you can use the same passwords) and make sure all ssid's, passwords and network device names are all alphanumeric (only). This takes care of possible 'microcode' differences that is stored on each connected device and may cause you issues when using different (not just 'newer') firmware, but the same ssid's.
    • With just a few devices on a particular network; you could elect to 'forget' and then re-associate each device with the router again, but a new ssid ensures you won't forget to do this. ;)
  • Even with the above steps, some handheld devices still need a 'reset network settings' to defaults to work properly with a router with new firmware (and sometimes new drivers).
  • Unplug all network equipment from the AC wall outlets and let them sit for 60 minutes or more if you can (minimum is at least 10 full minutes), including the modem, router, switches, NAS' and all clients/devices.
    • Now, plug in the modem and wait for 5 minutes for it to fully boot up.
    • Plug in the router and wait for 5 minutes for it to fully boot up and settle itself.
    • Plug in any switches and plug in and turn on all clients/devices (I suggest wired devices first).
If you do all the steps above and still have issues; more than likely any further glitches found will be real bugs to report, or, a wrong setup in the rest of your network (or specific devices).
 

Mihai Georgescu

New Around Here
I sent my router to the warranty and they sent me back a new one.
I have the same issue, i am unable to go over 100 mbs while using this router. I have a 1 Gb connection.

I flashed the router a couple of times, with Asus firmware and Merlin firmware, i reseted the factory defaults for 2-3 times, i cleared the NVRam using telnet.

I also did the Format JFFS partition at next boot and reboot the router.

What else can i do to make the router pass 100 mbs ?
 
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RMerlin

Asuswrt-Merlin dev
I sent my router to the warranty and they sent me back a new one.
I have the same issue, i am unable to go over 100 mbs while using this router. I have a 1 Gb connection.

I flashed the router a couple of times, with Asus firmware and Merlin firmware, i reseted the factory defaults for 2-3 times, i cleared the NVRam using telnet.

I also did the Format JFFS partition at next boot and reboot the router.

What else can i do to make the router pass 100 mbs ?
100 Mbps is a rather specific value, my guess is you only have a 100 Mbps link between the router and the modem. Replace the network cable with a better one.
 

Mihai Georgescu

New Around Here
100 Mbps is a rather specific value, my guess is you only have a 100 Mbps link between the router and the modem. Replace the network cable with a better one.
I have a 1Gb PPOE connection, if i plug in the cable directly in my mac, i have 998 MBs.
When i bought the router initially, i didn't had this issue, same cable and the speed was over 200 MBs on WiFi AC.
 

RMerlin

Asuswrt-Merlin dev
I have a 1Gb PPOE connection, if i plug in the cable directly in my mac, i have 998 MBs.
When i bought the router initially, i didn't had this issue, same cable and the speed was over 200 MBs on WiFi AC.
Still, try changing the cable. 100 Mbps is too specific a number not to dismiss the possibility. If the router's performance was the issue, you would be getting about 150-175 Mbps if for some reason you had NAT acceleration disabled or incompatible with your ISP.

Also, now you mention a wifi-based test. Make sure you test with an Ethernet connection, otherwise it's impossible to tell if your issue is with the wifi, or with the connection between the modem and the router.
 

Mihai Georgescu

New Around Here
I know this is old, I will write what was the issue.
Somehow the router was connecting at 100 mb/s, that was what the ISP company said. They came, had a look at the cable, and just tighten up a bit the ethernet plug, and that was all.
What is strange is that it was working on the macbook, it was connecting at 1 gb connection.
After this fix speed is approximately the same Direct or Through Router.
 

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