We have a SFTP server which was working fine until we added another ISP. The connection to the SFTP server is not going through the new ISP, I confirmed it with
tracert. No change was made on the server either. But since then, some users' SFTP or SSH connections time out/hang if the executed command has a larger return. Here's the scenario:
- I can continue to ping and the ping will always return even when SSH/SFTP times out
- I can connect to the server, it asks for authentication and lets me log in.
- If the
lscommand for my root directory is returning a small number of files or folders, then it shows the listing of files and folders
- If the
lscommand for my root directory is larger than let's say 5 or 6 files or folders, then it hangs/times out.
- While trying this, I tried running a ping to the server, and it's returning all the time.
This doesn't happen to everyone, but it seems to happen to users who are in another city..
I tried different SFTP clients (FileZilla and WinSCP). Both have the same issue.
I ran WireShark on my PC (which is outside of our network and outside of the city), when SFTP/SSH times out, I see retransmission and part of segment not captured errors coming up, which leads me to believe there might be some packet loss somewhere between the hops.
Expert Info (Note/Sequence): Retransmission (suspected) Previous segment not captured (common at capture start)
Is SFTP/SSH that sensitive to packet loss? Wouldn't SSH/SFTP retransmit/reacknowledge to avoid these packet loss errors? Is there something on the server settings I can tweak in order to make this work?