Hello, I'm experiencing strange behavior on ssh-enabled file transfers (scp and rsync): When connecting to the Internet through an RTC PPP link to a certain provider, file transfers from a remote host (debian potato) to my local host (debian woody) get immediately stuck when issued from the local host, while they work very well when issued from the remote host. On the other hand, no problem with shell connections nor with rsync dry-runs. Also, if I connect to another provider, everything works as expected. Do you have any idea of what might happen? Thank you very much in advance, Xavier
Xavier Cazin wrote:> When connecting to the Internet through an RTC PPP link to a certain > provider, file transfers from a remote host (debian potato) to my > local host (debian woody) get immediately stuck when issued from the > local host, while they work very well when issued from the remote > host.Is there a firewall or packet filter? If there is then it might be an MTU problem. Check the MTU on both your PPP interface and remote host's ethernet and set the higher one to equal the lower (or drop both to 576 and work up until it breaks). Also check both hosts to see if their path MTU discovery is enabled (cat /proc/sys/net/ipv4/ip_no_pmtu_disc should be 0). You might need to play with the MTU settings as this can be something of a black art due to the number of variables: host behaviour, mtu's, pmtu discovery, firewall behaviour, every link MTU between hosts, phase of the moon.... you get the idea. -Daz.