Hi everybody,
any help with the following issue will be greatly appreciated.
my old configuration: PC --- Fritzbox Router --- TP-Link DualWAN Router --- Internet --- (ftp server of web space provider )
both routers had NAT enabled. Updating files on my web space using ftp upload from my PC was seamless. FTP ALG enabled on DualWAN Router.
new configuration: PC --- Fritzbox Router used as switch --- TP-Link DualWAN Router --- Mikrotik SXT5 Lite Router --- Fritzbox2 Router --- internet --- (ftp server of web space provider)
all routers have NAT enabled. Mikrotik has FTP Helper enabled, newest firmware and RouterOS 6.4. FTP ALG enabled on DualWAN Router.
Configuration works flawlessly in both up- and download data.
However: uploading data from PC using filezilla ftp client in passive mode to ftp server of my web space provider produces timeouts. Let’s say 5 consecutive files are uploaded without any problems, then communication stops, timeout occurs after about 15 s. As filezilla supports “retrying” the files are uploaded after some retries. Next 10 files are uploaded without problems, then timeout occurs again.
Uploading using my web page generator with built-in ftp with limited number of retries is impossible due to many timeouts.
I assume the ftp uploading problems stem from Mikrotik. I read in this forum that ftp protocol may have issues but I thought enabling FPT Helper (it is enabled by default) would solve any related issues. Do I need some manual tweaking of port forwarding or NAT or firewall?
As my web page generator is useless now I would be grateful for any hint.
Thanks
Today, I tried an alternative configuration. I attached an ASUS RTn16 Router with DDWRT to the second WAN input of my DualWAN Router. So I am able to subsequently test internet access using either Mikrotik or Asus RTN16 to find out whether the ftp uploading problem is caused by Mikrotik SXT5 Lite CPE or other elements.
Here is my alternative architecture:
new configuration: PC --- Fritzbox Router used as switch --- TP-Link DualWAN Router --- Mikrotik SXT5 Lite Router OR ASUS RTN16 DDWRT --- Fritzbox2 Router --- internet --- (ftp server of web space provider)
After testing some FTP uploads it was obvious that my ftp uploading problem is definitely only with Mikrotik. With ASUS RTN16 DDWRT: no problem.
As ftp helper is enabled in MT I have no clue what is going wrong with Mikrotik. It is a rather weird problem as uploading is possible for say 5 files then a timeout occurs. Problem is a bit less severe if I limit ftp uploading to 1 file at a time. This way, less ports are used for uploading.
Therefore, I assume that something is wrong with the specific FTP HELPER implementation in MT. However, this should be a common problem as ftp uploading over NAT is a general procedure and should occur for many people.
Any hint? Thanks in advance.
I would like to post my new results.
I altered the MikroTik configuration from router to bridge mode. Now ftp uploading is flawless. This is another strong hint that NAT implementation in SXT 5 lite has an ftp issue.
Edit: Another observation of bridge mode is an amazing improvement in browsing speed of very complex websites with much text and graphics. I have no clue why.