unable to download some http content

Hi all,

I have a weird problem (or so it seems).
I can’t download the following URL from a Vyos1.1.8:

The above is an example of a URL which I can’t download from vyos itself or a device connected to it (vyos acts as a router). Here are the clues to build the case:

  • It is not a firewall problem. I have removed all the firewalls from interfaces
  • The vyos has an internet-facing interface with a public IP and a default gateway.
  • Vyos actualy opens the TCP connection with the 'download.proxmox.com’ host… I have captured a TCPDUMP and I can see the initial packet exchange. The exchange stops when the server download.proxmox.com starts sending the data packets of the ‘packages’ file. I never see the packets in tcpdump.
  • The same happens with an debian installation that is behind Vyos. The debian has also public IP, so it is not a NAT thing. The debian succeeds to download the url, when I replace the Vyos router with another device.
  • The 'download.proxmox.com’ is really working. I have downloaded the file from the debian and other machines, when vyos is not in the middle (is not the router).
  • I can download from Vyos other URLs fine.
  • The Vyos is in production and does not seem to have any other problems.

It is very weird. It must be something very obvious or something very evil…

Any ideas?

Vyos 1.1.8 (it happens on earlier versions too).