How to Transfer a 200GB File Over LAN Fast: Comparing scp, rsync, wget, and bbcp

In a LAN environment the author tested copying a single 200 GB file using several tools and recorded their performance.

Methods tried:

Method 1: scp

scp (secure copy) uses SSH for authentication and encryption. Initial transfer speed was about 33 MB/s for a few minutes, then dropped to around 3 MB/s.

Method 2: rsync

rsync is a high‑efficiency remote‑data backup tool. In this test it showed no response.

Method 3: wget

wget is a non‑interactive command‑line downloader supporting HTTP/HTTPS/FTP and resume. It started at about 50 MB/s but fell to roughly 3 MB/s after a few minutes.

Method 4: bbcp

bbcp, developed at SLAC, is a point‑to‑point network file copy tool. In a test copying a 20 GB file it achieved an average speed of about 21 MB/s, completing in 16 minutes, roughly ten times faster than scp.

Conclusion: Choose the tool that fits the scenario; for large single files bbcp performed best.

Installing bbcp on both ends

wget http://www.slac.stanford.edu/~abh/bbcp/bin/amd64_rhel60/bbcp -O /usr/bin/bbcp
chmod +x /usr/bin/bbcp

Key bbcp options (from Chinese documentation)

-k keep incomplete files and allow overwriting on retry

-a keep checkpoint information for integrity verification

-r recursive transfer of directories

-P 2 display progress every two seconds

-V print debug information

-f force removal of failed data on remote host

-w set disk I/O buffers (algorithm: window = netspeed/8*RTT = … ≈ 9.25 M)

-s 16 set concurrency to 16 (official recommendation)

-T "ssh -x -a -p 2222 -oFallBackToRsh=no -i /home/dong.guo/.ssh/id_rsa -l heydevops heylinux.com /usr/bin/bbcp"

Authentication details: use port 2222, disable fallback to rsh, specify SSH key, and login user.

Reference documents:

http://pcbunn.cithep.caltech.edu/bbcp/using_bbcp.htm

http://heylinux.com/archives/2984.html

http://imysql.cn/2008_12_08_using_bbcp_instead_scp

http://linux.cn/article-4527-1-rss.html

http://teachmyself.blog.163.com/blog/static/188814229201242314917237/