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View Full Version : Bug: using FTP command-line client exposes signed 32-bit bug



HansSchulze
11-20-2011, 07:37 PM
I recently telnet'd into Javelin S4 in an attempt to back up another NAS, and found that the command line FTP client has some issues:
- "binary" then "get filename" of a 3.35GB (3602001920) byte file shows a message "150 3517580.0 kbytes to download". Then a message "Local: (filename) short write", then "450 Error during write to data connection". The target file was exactly 2GB. Repros consistently with different files. WinXP FTP client doesn't have this issue.
- "mget *" cannot transfer any files with spaces in the file name, possibly known issue, but should be fixed.
- The NAS replication GUI isn't straight-forward enough, no idea how to specify paths to backup, nor what all the modes mean. No online help with a sentence to describe each mode. No place to input a login name/password for the source NAS. It seems that this service is only for Javelin-to-Javelin backups, not a very common case.
- Speed is only 88 mbits/sec even though SAMBA gets almost twice that, using 9k jumbo packets. The last attempt at NAS to NAS backup was using WinXP and MS SyncToy, which at least lets me know which files are still missing, and allows comparing binary to make sure the copy was perfect. Still, this means 30 hours per terabyte. I would have hoped that FTP might be closer to metal speeds. Is there an alternative that I can use between two dissimilar NAS?
I will try WinXP to run PASV and post results.

HansSchulze
11-20-2011, 09:51 PM
http://www.wftpserver.com/download/ftprush.exe did the job using FXP / PASV as simple as SyncToy would have. No issues with huge files. Transfers two files at a time, about same net speed as a single FTP transfer. Thank the persistent types that write software like that. :)
Both NAS are 9K packets, seeing about 20% CPU utilization per FTP on "from" NAS, and 2% on Javelin.

HansSchulze
11-22-2011, 05:02 PM
There might still be an issue with my unit, my machine, or the Javelin. Running FXP mode for about 5 hours at ~90Mbits/sec seems to lose connection of both the FTP software and SAMBA connection from the monitoring host WinXP system, although it's easy to bring back with just reopening the connections. I will try another machine/OS as the host, as well as trying SyncToy.