Mikrotik RB751 Wifi problems

isie

isie

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Hi Guys
Any one else find the WiFi on the RB751U-2HnD horrible to use?
From what I can figure out first of all its very slow and it seems to cause Watchdog to reboot the router if too much traffic goes via WiFi.
On normal internet its fine (sort of i have noticed a few reboots though) but if i try to send a huge file from my Laptop to a PC via the network, its extremely slow and eventually crashes)


My current Setup

Rb751 - port 1 and 5 connected to my Iburst modems with a fail over script (not load balancing yet having trouble with that) - WiFi on Chanel 1+5 (B G and N)
Port 2 connected to my Linksys Wtr54g router (standard firmware) (need this as I ran out of ports for all the devices on the Mikrotik) Originally disabled the WiFi.
Port 3 and 4 connected to a few devices and a few other devices connect to the Linksys (Xbox, Bluray etc).

I have another Linksys WRT54g2 router downstairs running DD-WRT operating as a wireless bridge basically for my stuff downstairs (Bluray) with out WiFi (basically receives WiFi from Mikrotik converts to Ethernet) picks up Channel 1 on WiFi (G only).

So Decided to set up a simple media server this weekend connected it to Linksys put a few files on there and tested works fine streams OK.

Then tried to send files over the network from my laptop to the Media server transfer speed was horrible (less then 1MBps) and after a minute or 2 Mikrotik would reboot. So then switched on the WiFi on the Linksys - used same SSID on Channel 10 - tried files again, Connected to the Mikrotik, it crashed Laptop automatically switched over to the other router and transferred the files at a decent speed of 4 or 5 MBps (Wireless G) - SO figured the Other router connecting to the Mokrotik was the problem, so swapped all that, changed the Mikrotik to Channel 6+10 and the Linksys to channel 1 (G only) ( I scanned the WiFi channels using Inssider and these were the best options for both). tried a file and same story Mikrotik transfer under 1Mbps then Crashed and Laptop switched over to the other one, this time transfer speed was 1 or 2 MBps (assume due to it being connected to the other Linksys i only have access to 1/2 the available bandwidth) Tried changing the Mikrotik to N only still same result.

I didn't try using a wired connection to transfer files, was busy with this till late last night will try it tonight but have a feeling it is the WiFi - every now and again my laptop would have trouble connecting to the WiFi and after a while will finally connect, and my phone would get an authentication error, since using the Linksys they connect to that first and after a while would connect directly to the Mikrotik as it is the 'better' connection as it were.

Any one no if there is a setting or script Im missing in the Mikrotik that Handels traffic from WiFi ?
oh and complicated as this setup may sound I have no idea what I'm doing - :D
 
Hi Isie,

The 751's wireless is horrible, it hasnt got the best reviews on the net this RB. If you want something more powerful and capable. I stream 1080p movies flawlessly using this router. Let the MT(mikrotik) do other functions like load balancing. You want some help with the load-balancing? Post instructions here for google heathen to search and find.
 
I remember when I bought my RB751G. The guys here at work first wanted to do some testing, and they had numerous problems with the Wifi to the RB751G. It was still on Router OS 4.x back then.

When I took it home, I moved over the Router OS 5.x and it is now on Router OS 6.0. I personally haven't had a single issue with it, except if I use channel 13 it seems some Android devices fail to connect to the wireless, but everything else seem to work 100%. That said, I mostly only use my Nokia N9 on it.
 
I dont have issues with the rb751g, maybe some external ariels would help? e.g like the rb2011UAS - that wifi rocks!
 
Peon said:
Hi Isie,

The 751's wireless is horrible, it hasnt got the best reviews on the net this RB. If you want something more powerful and capable. I stream 1080p movies flawlessly using this router. Let the MT(mikrotik) do other functions like load balancing. You want some help with the load-balancing? Post instructions here for google heathen to search and find.
Click to expand...

Dont have the Budget for another router and just recently purchased the Mikrotik, as it was the one recommended for load balancing - which BTW i have googled like no ones business and not getting anywhere - haven't given up though just sidelined in the mean time. As for streaming, for My Full HD stuff The TV is close to the server and router so hard wired connection is fine, the WifI is just for my downstairs TV which i use for watching the regular sub720 videos - which so far is fine. - Its actually transferring stuff from one PC to the other over the network - I can just copy to MY USB HDD and then walk upstairs but I'm trying to not do that :).
I was trawling the Mikrotik forums found a few people had similar problems, but no one had an actual solution besides update to latest OS which I have already done.

Tinuva said:
I remember when I bought my RB751G. The guys here at work first wanted to do some testing, and they had numerous problems with the Wifi to the RB751G. It was still on Router OS 4.x back then.

When I took it home, I moved over the Router OS 5.x and it is now on Router OS 6.0. I personally haven't had a single issue with it, except if I use channel 13 it seems some Android devices fail to connect to the wireless, but everything else seem to work 100%. That said, I mostly only use my Nokia N9 on it.
Click to expand...
Router has latest version OS 6.2 - AFAIK Chanel 13 is a little tricky, had a laptop that wouldn't connect on that channel once.


paul5186 said:
I dont have issues with the rb751g, maybe some external ariels would help? e.g like the rb2011UAS - that wifi rocks!
Click to expand...

The Router does have the option of adding an Externa Antennae, just not sure of the size that will work - the connector is allot smaller then the one on the Linksys - but I doubt it will help, its not like the distance is an issue Its not a huge house and honesty the broadcast distance of the WifI is pretty good picked up my WifI signal quite a distance away from my home the other day.


Are them some firewall rules that govern the traffic that could be the issue?
 
Try this

check both chains RX and TX,
put antenna mode on A,
put it on B/G/N 20/40Mhz Above
play with the TX power, normally low TX power gives better throughput

I have one as my home AP and get about 4-5MBps (bytes not bits)
 
isie said:
The Router does have the option of adding an Externa Antennae, just not sure of the size that will work - the connector is allot smaller then the one on the Linksys - but I doubt it will help, its not like the distance is an issue Its not a huge house and honesty the broadcast distance of the WifI is pretty good picked up my WifI signal quite a distance away from my home the other day.
Click to expand...

You will need an antenna with a mmcx connector like this http://www.scoopdistribution.co.za/product_info.php?products_id=1087

Make sure your mode is 802.11b/g/n and 40Mhz
 
nerf said:
Try this

check both chains RX and TX,
put antenna mode on A,
put it on B/G/N 20/40Mhz Above
play with the TX power, normally low TX power gives better throughput

I have one as my home AP and get about 4-5MBps (bytes not bits)
Click to expand...

Thanks will try - and ill be fine with 4-5MBps - I'm assuming that's connecting on Wireless G - N should be significantly faster
 
What sort of Overall Tx CCQ (interface/status) are you getting when transferring the files.
For indoor links with routeros I find setting the HW retries on the interface up to 15 improves transfer speed and stability
 
Are you on the latest RouterOS? I currently have openwrt installed on mine, never had issues on RouterOS as well. How strong is the signal from the devices you connect from? Although the antennas is small, it covers my flat fully.
 
nerf said:
Try this

check both chains RX and TX,
put antenna mode on A,
put it on B/G/N 20/40Mhz Above
play with the TX power, normally low TX power gives better throughput

I have one as my home AP and get about 4-5MBps (bytes not bits)
Click to expand...
]

other settings were already the same as you mentioned, tried dropping tx and still crashed :(

pojo2 said:
What sort of Overall Tx CCQ (interface/status) are you getting when transferring the files.
For indoor links with routeros I find setting the HW retries on the interface up to 15 improves transfer speed and stability
Click to expand...

changed HW to 15 same result crash :(

krieg said:
Are you on the latest RouterOS? I currently have openwrt installed on mine, never had issues on RouterOS as well. How strong is the signal from the devices you connect from? Although the antennas is small, it covers my flat fully.
Click to expand...

OS v 6.2 and actual Wifi signal is great and coverage goes far , but problem as mentioned as soon as i try sending a large file thing dies!

And confirmed its the WiFi tested a few files with laptop connected via Ethernet , no problems transferring decent speed no crash
 
Only other thing I can think of is going to System-Routerboard and upgrade the firmware if there is a new version available
 
isie said:
Dont have the Budget for another router and just recently purchased the Mikrotik, as it was the one recommended for load balancing - which BTW i have googled like no ones business and not getting anywhere - haven't given up though just sidelined in the mean time. As for streaming, for My Full HD stuff The TV is close to the server and router so hard wired connection is fine, the WifI is just for my downstairs TV which i use for watching the regular sub720 videos - which so far is fine. - Its actually transferring stuff from one PC to the other over the network - I can just copy to MY USB HDD and then walk upstairs but I'm trying to not do that :).
I was trawling the Mikrotik forums found a few people had similar problems, but no one had an actual solution besides update to latest OS which I have already done.
Click to expand...
Apologies for going off topic, but I'm planning to buy the 951G next week.
By load balancing, do you mean giving priority to traffic, ie P2P, streaming, gaming, etc?

That is what I would like to do and I have zero experience with that router and networking in general.
Would you advise me against it, because I'm also going on what have been mentioned in posts.

Edit:
Is the wireless on the 951G better?
 
Last edited:
The wireless on the 751 works fine and there must be a configuration issue or network loop for the watchdog to reboot. Connect one device through wireless and test the speed to one device plugged in to Ethernet. If it still reboots reset to default and try again. If it still reboots send the automatically generated supout to support at mikrotik dot com
 
Question:
What was the reason for setting up the watchdog timer?
To which device is the IP pointing?

I would disable the watchdog first and then see what it does.
Sometimes it also help to lower the TX power as you get less noise then as well.

Try and get Netstumbler running on your laptop and monitor your area.
I have found that some N type devices, not MT, like to jump freq automatically to try and get more speed, but this can cause other devices in the area problems.

Also having 2 WiFi devices with the same SSID in the same area can also cause the devices to get confused, if there is not a management system in place.
 
perhaps reset it to factory default and start over. Make sure you use AES instead of TKIP if you use encryption. TKIP slows everything down
 
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