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| Subject | JaSFtp issue with GlobalScape Secure Ftp server 2.0 |
| Date | 08/15/2006 |
| Message | From GlobalScape, we have their
Secure-ftp-Server 2.0. If I connect the JaSFtp-Client with ftp-protocol,
we can view and transmit, from ftp-server to the client, a folder with
3580 small (2KB) files. But if I connect with sftp, then I d'ont see any
files in the same directory. If I reduce the amount of files to 40
files, then I see the files in the directory.
If I install the ftp-client from GlobalScape, then I see all files in the directory. I evaluate your software and it is a very good tool for our solution. I hope, you can help me. Best Regards |
| Reply1 |
1) Yes, I did test a folder with about 5500 files and I had no
problems.
2) Does the directory listing fail for the manual SFTP browser only? or a SFTP task to this folder also fails? 3) Try to view this folder again using the SFTP browser. If the files do not show, look at the Logs menu / Debug log. See if there are any entries there and send that to me. -- Sincerely, Melvin Desilva Hitek Software
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| Reply2 |
Hi Melvin
I was out of the office and today I tried it again. But the problems are the same. I send you the debug Log attached. Are you using the sftp-Server from GlobalScape or another? Thanks for your help and Best Regards May 3, 2005 11:25:00 AMcom.maverick.ssh.SshException: Unknown |
| Reply3 |
Hi Walter,
I forwarded the error information to my 3rd party api supplier. They have scheduled a few tests against GlobalScape and will get back to me when it is done. -- Sincerely, Melvin Desilva Hitek Software
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| Reply4 |
Hi Walter, Our 3rd party vendor 3sp.com has responded. Please see below. Though it is a problem with GlobalScape, they will provide an option in their api which they think will fix this issue . Then I will have to include their new api. with a JaSFtp patch update to include this option in the JaSFtp server profiles. All this may take about 1-2 months. So, this fix will only be in JaSFtp Version 6.18-6.20. -- Sincerely, Melvin Desilva Hitek Software --------------------------------------------------------------------------------------- Hi Melvin, I have taken a look at the Globalscape SFTP server and located the source of the problem. Our API is throwing a protocol violation exception because the server is sending a transport layer packet in the region of 85000 bytes. The maximum size of transport packets currently supported by Maverick is 35000 bytes. This figure is taken from the SSH specification as the recommended figure for implementations to support. The specification does not restrict packets to this size and it does allow implementations to use higher packets although it states that "larger packets MAY be sent if the version string indicates that the other party is able to process them". I think that Globalscape have mis-interpreted the spec here, there is a seperate channel mechanism on which the SFTP protocol operates and this does support higher packet sizes, but these should be broken into smaller packets for the transport layer. I am not convinced that Maverick should support higher packet levels by default since this is the first instance of a protocol violation of this kind we have seen. I have been able to resolve the issue by adding an additional field to the SSH2 context which allows the maximum packet size to be set. Changing this to a higher value of 100,000 bytes allows the Maverick API to support the Globalscape server but I expect that several clients will have issues with their implementation. A new build containing this workaround will be available within the next couple of weeks. Regards |
| Reply5 |
Hi Melvin Thank you for your answer. Therefore I will wait, until the new version appears. |