Net::SFTP hangs when downloading a file

Ruby
1

I have some code which attempts to download some data from an sftp
server and it hangs. Once it hangs it seems to lock up the entire
process so the timeout is not working either. The code hangs at the
session.download! method (debug output below)

The same code works for other servers and even other directories on
the same server so this is very baffling to me.

I am using ruby 1.9.3 but I have also tried it with ruby 1.8.7. The
Timeout::timeout wrapper doesn’t do anything since the blocking is
apparently locking up the entire process.

debug output

sending open packet (2)
queueing packet nr 13 type 94 len 92
sent 116 bytes
read 68 bytes
received packet nr 15 type 94 len 44
channel_data: 0 17b
received sftp packet 102 len 13
sending read packet (3)
queueing packet nr 14 type 94 len 44
sent 68 bytes
read 1358 bytes
read 742 bytes
received packet nr 16 type 94 len 2076
channel_data: 0 2048b
received sftp packet 103 len 2044
sending read packet (4)
queueing packet nr 15 type 94 len 44
sent 68 bytes
read 52 bytes
received packet nr 17 type 94 len 28
channel_data: 0 2b
read 84 bytes
received packet nr 18 type 94 len 60
channel_data: 0 32b
sending close packet (5)
queueing packet nr 16 type 94 len 44
sent 68 bytes
read 68 bytes
received packet nr 19 type 94 len 44
channel_data: 0 28b

2

I have recently had also some problems with Net::SFTP.

Cannot help with this hang, but just in case remember that OpenSSH
installs the command-line client sftp(1). With that client you can check
whether the hang can be reproduced. If it does maybe the problem is not
in the client side. Otherwise, it gives an alternative if shelling out
is an option.

Enviat des del meu iPad

El 6 Jun 2012, a les 05:54, Tim U. [email protected] va escriure:

3

I really wanted to avoid shelling out. That seems like such a cop out.
What’s worse is that Timeout doesn’t work in both ruby 1.9 and ruby
1.8 when trying to deal with this. I am trying to get Terminator to
work but not having a lot of luck with that either.