globftp | HPC @ LLNL

This page describes the usage of globftp, an LC-developed tool which enables parallel transfers to LC's Globus endpoint. Since the globus endpoint is in the "green" network, other data transfer mechanisms (e.g., scp) are not optimized for performance. Globftp transfers data strictly between the CZ OSLIC cluster and the Green cluster Goblin containing the LC Globus endpoint file system. NOTE All data transferred to Globus/Goblin must be authorized, see the review and release guidance.

User Walk Through

Users needing to transfer very large amounts of data to goblin / globus should use the LC-developed globftp tool. This tool is configured for LC systems and will enable a parallel ftp transfer between the oslic and goblin clusters.

Prerequisites

As outlined on the Globus user documentation page, users must request accounts via LC IDM to goblin cluster. To authenticate to the Globus web-frontend, users will need LLNL Active Directory credentials.

Data that is transferred from LC systems to the goblin / globus system should follow appropriate review and release guidance.

Basic globftp Usage

The globftp tool is a frontend for the regular ftp interactive command-line tool. By using globftp, users can ensure their large transfers are performed in parallel. When using FTP, users should be aware of a few modes of operation that must be explicitly set to ensure best performance.

Users need to run ftp in "passive" mode, to ensure that command results are properly received by the local terminal. This mode can be toggled with the passive command, it is recommended that user ensure passive mode is OFF.
Users probably do not want to use interactive mode, which can be toggled with the prompt command. With interactive mode OFF, users will not be prompted when requesting a recursive transfers (that is, transferring files within directories and subdirectories).

Available ftp commands can be listed with ? and details on a command can be shown with ? command-name.

Example Usage

This example walks through a large file transfer using the globftp tool. Command usage and resultant output examples are shown.

Step 1. Use the globftp tool.

This must be run from oslic where users will be prompted for their username and CZ password (PIN+RSA Token).

11:32:53 gonsie@oslic3 ~ $ globftp
Connected to goblin2.llnl.gov.
220-NOTICE TO USERS
[[ ... ]]
220 goblin2 FTP server (HPSS 9.3.0 Parallel FTP Daemon) ready.
GSSAPI accepted as authentication type
Name (goblin2:gonsie):
331 Password required for gonsie.
Password:**************
230 User gonsie logged in as gonsie@llnl
Remote system type is UNIX.
215 Parallel protocol is PDATA_AND_MOVER
ftp>

Step 2. Toggle ftp modes for best performance.

Users should enter "passive" mode to run commands such as ls and pwd.

ftp> passive
Passive mode on.
ftp> cd /p/globfs/gonsie
250 CWD command successful.
ftp> pwd
257 "/p/globfs/gonsie" is current directory.
ftp> ls -al
227 Entering Passive Mode (192,12,137,22,160,70)
150 Opening ASCII mode data connection for file list.
-rw-r-----   1 gonsie     gonsie          10687086592 Feb  3 11:34 ior-corona.00000000

Users needed to do recursive transfers should toggle interactive mode OFF.

ftp> prompt
Interactive mode off.
ftp>

Step 3. Stage file transfers.

Users can run the lcd command to change directory on oslic (the local connection):

ftp> lcd /p/lustre1/gonsie
Local directory now /p/lustre1/gonsie
ftp>

Users can send large files with the send or put commands

ftp> send ior-corona.00000000
200 Command Complete (10687086592, "ior-corona.00000000", 5, 12, 4194304).
local: ior-corona.00000000 remote: ior-corona.00000000
200 Command Complete.
200 Command Complete.
200 Command Complete.
200 Command Complete.
200 Command Complete.
200 Command Complete.
200 Command Complete.
200 Command Complete.
200 Command Complete.
200 Command Complete.
200 Command Complete.
200 Command Complete.
150 Transfer starting.
226 Transfer Complete.(moved = 10687086592).
10687086592 bytes sent in 9.929 seconds (1.076 gbytes/s)
200 Command Complete.
ftp> send ior-corona.00000001
200 Command Complete (13455327232, "ior-corona.00000001", 5, 12, 4194304).
local: ior-corona.00000001 remote: ior-corona.00000001
200 Command Complete.
200 Command Complete.
200 Command Complete.
200 Command Complete.
200 Command Complete.
200 Command Complete.
200 Command Complete.
200 Command Complete.
200 Command Complete.
200 Command Complete.
200 Command Complete.
200 Command Complete.
150 Transfer starting.
226 Transfer Complete.(moved = 13455327232).
13455327232 bytes sent in 6.312 seconds (2.132 gbytes/s)
200 Command Complete.
ftp>