Max Concurrent Router to NAS FTP Download

RouterOS Scripting
1

Hi There,

I’ve done a ton of reading and can’t find details anywhere close to resembling my issue. I have 150-200 Mikrotik RB952s or hAPAC2s routers running a script at 3:00 AM that starts with downloading a file (less than a MB) from the local LAN Mikrotik NAS RB4011 files directory. The Script works perfectly for each device when I run it individually, however when they all run at the same time i.e. 3:00AM about 10% of them fail to download the file. Is there a default simultaneous ftp connection limit from router to router? My firewall rule allowing the ftp traffic does NOT have any connection limits set. I’m running v7.12 on all devices.

Thanks for any assistance in advance. :slight_smile:

2

Just a follow up on the above. It appears that since the APs are all trying to download the same file at the same time this is where the error may be occurring. Does anyone know if there is a limitation to the number of devices that can connect to a Mikrotik 4011 using ftp and download the same file at the same time or is this a limitation of the file itself? It’s a script .rsc file?

3

In general it is just wrong to have all the equipment do something like this at the same time.

  1. There may be a limit.
  2. There may be a limit in the future.
  3. Unnecessary peak in traffic and resources

The solution is simple:
spread requests over a longer period of time, where each device downloads at a given time, perhaps based on the device’s ether1 MAC address.

Simple example: if the MAC is odd, the download occurs at 03:00, if it is even, the download occurs at 03:05.

4

Thanks rextended good points.

I’ve edited the scheduler for the script by making the run time randomised during a period i.e. 1AM-5AM every 15 days. So now it works flawlessly.

It appears that even though the file I was trying to have the NAS download was only 400Kb the file structure itself doesn’t lend to being downloaded multiple times at the same time by multiple devices. it wasn’t a Mikrotik or Network error but simply a limitation of the file itself. The larger the file the more failures so randomising WHEN they download it solved the issue.