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Multiple simultaneous downloads using Wget?

I'm using wget to download website content, but wget downloads the files one by one.

How can I make wget download using 4 simultaneous connections?

A similar question with a nice solution: stackoverflow.com/questions/7577615/parallel-wget-in-bash
Have a look at this project github.com/rockdaboot/wget2
For those seeing the above comment regarding Wget2, please use the new repository location: gitlab.com/gnuwget/wget2. It is the official location for GNU Wget2, the spiritual successor to Wget

C
Coc B.

use the aria2 :

aria2c -x 16 [url]
#          |
#          |
#          |
#          ----> the number of connections 

http://aria2.sourceforge.net

I love it !!


I don't see how this helps download a website - it looks like it only downloads 1 file. If this is true - the votes should be -ve.
I agree, this is not a good answer, because aria2 cannot do web or ftp mirroring like wget or lftp. lftp does mirroring as well as supporting multiple connections.
Don't forget -s to specify the number of splits, and -k to specify the minimum size per split segment - otherwise you might never reach the -x max connections.
@Stephen this is to download very large files much faster from websites by using multiple sockets to the server instead of one. This is not mean for scraping a website.
does not supports socks*
O
Olivier Pons

Wget does not support multiple socket connections in order to speed up download of files.

I think we can do a bit better than gmarian answer.

The correct way is to use aria2.

aria2c -x 16 -s 16 [url]
#          |    |
#          |    |
#          |    |
#          ---------> the number of connections here

Official documentation:

-x, --max-connection-per-server=NUM: The maximum number of connections to one server for each download. Possible Values: 1-16 Default: 1

-s, --split=N: Download a file using N connections. If more than N URIs are given, first N URIs are used and remaining URLs are used for backup. If less than N URIs are given, those URLs are used more than once so that N connections total are made simultaneously. The number of connections to the same host is restricted by the --max-connection-per-server option. See also the --min-split-size option. Possible Values: 1-* Default: 5


To document -x, --max-connection-per-server=NUM The maximum number of connections to one server for each download. Possible Values: 1-16 Default: 1 and -s, --split=N Download a file using N connections. If more than N URIs are given, first N URIs are used and remaining URLs are used for backup. If less than N URIs are given, those URLs are used more than once so that N connections total are made simultaneously. The number of connections to the same host is restricted by the --max-connection-per-server option. See also the --min-split-size option. Possible Values: 1-* Default: 5
Thanks for elaborating on the parameters, Nick.
The option -s alone no longer split a file from a single server since the 1.10 release. One needs to use --max-connection-per-server together to force establish multiple connections. See aria2 documentation: About the number of connections Since 1.10.0 release, aria2 uses 1 connection per host by default and has 20MiB segment size restriction. So whatever value you specify using -s option, it uses 1 connection per host. To make it behave like 1.9.x, use --max-connection-per-server=4 --min-split-size=1M.
The shorthand of @SamuelLi's update is aria2c -x 4 -k 1M url and worked well for me (a server with a limit of 100k per connection let me download at 400k with said parameters)
Critically, aria2 does not support recursive HTTP downloads, making it a substandard replacement for wget if -r is desired.
N
Nikolay Shmyrev

Since GNU parallel was not mentioned yet, let me give another way:

cat url.list | parallel -j 8 wget -O {#}.html {}

That's interesting approach. Not really applicable when you need to download a huge file and you get limited speed per connection, but can be useful when downloading multiple files.
Running this command would run the list 8 times, no? I did it the same way and instead of processing each line with 8 parallels, it just processes the whole list 8 times.
No, it splits the list on 8 jobs
Okay, I'm definitely doing something weird. Will figure it out. Thanks for the quick response.
That's a useless use of cat, though. In this limited context, it's quite harmless, but maybe you don't want to perpetrate this antipattern.
a
aioobe

I found (probably) a solution

In the process of downloading a few thousand log files from one server to the next I suddenly had the need to do some serious multithreaded downloading in BSD, preferably with Wget as that was the simplest way I could think of handling this. A little looking around led me to this little nugget: wget -r -np -N [url] & wget -r -np -N [url] & wget -r -np -N [url] & wget -r -np -N [url] Just repeat the wget -r -np -N [url] for as many threads as you need... Now given this isn’t pretty and there are surely better ways to do this but if you want something quick and dirty it should do the trick...

Note: the option -N makes wget download only "newer" files, which means it won't overwrite or re-download files unless their timestamp changes on the server.


But doesn't that download the whole set of artifacts for each process?
@KaiMattern: add the -nc option: "no clobber" - it causes wget to ignore aready downloaded (even partially) files.
I had a list of images I needed to download, and this worked for me as well: wget -i list.txt -nc & wget -i list.txt -nc & wget -i list.txt -nc Very ugly, but hey, it works. :P
Having one of those connections broken for some reason gives you uncompleted files, without touched by other connections. This method creates integrity issues.
The -b flag will run the wget process in the background, as an alternative to bash's & job control built-in. STDOUT will be written to wget-log if -o <filename> is not specified. Good for scripting. See wget(1) for more details.
L
Lord Loh.

Another program that can do this is axel.

axel -n <NUMBER_OF_CONNECTIONS> URL

For baisic HTTP Auth,

axel -n <NUMBER_OF_CONNECTIONS> "user:password@https://domain.tld/path/file.ext"

Ubuntu man page.


this program allows unlimited numbers of connections which is very useful in some cases.
Axel cannot do HTTP basic auth :(
I usually do axel -n 4 "user:pasword@http://domain.tld/path/file.ext"
can i use axel for recursively download a whole folder?
r
rogerdpack

A new (but yet not released) tool is Mget. It has already many options known from Wget and comes with a library that allows you to easily embed (recursive) downloading into your own application.

To answer your question:

mget --num-threads=4 [url]

UPDATE

Mget is now developed as Wget2 with many bugs fixed and more features (e.g. HTTP/2 support).

--num-threads is now --max-threads.


Nice find. Thank you!
any tips on how to install wget2 on a mac? Site only documents how to install it from source and having trouble getting autopoint
In out TravisCI script we use use homebrew to install gettext (which includes autopoint). Have a look at .travis_setup.sh from the wget2 repo.
Great! I like how this did recursive downloads, and worked with my existing wget command. If you have difficulty compiling wget2, an alternative might be to use a docker image.
r
rr-

I strongly suggest to use httrack.

ex: httrack -v -w http://example.com/

It will do a mirror with 8 simultaneous connections as default. Httrack has a tons of options where to play. Have a look.


@aaa90210: It'd be great if you'd have succinctly explained the programs deficiencies. ArturBodera's comment is much more informative.
@ArturBodera You can add cookies.txt file to the folder your are running your program from and it will automatically add those cookies to the download header.
httrack does not support following redirects
r
runejuhl

As other posters have mentioned, I'd suggest you have a look at aria2. From the Ubuntu man page for version 1.16.1:

aria2 is a utility for downloading files. The supported protocols are HTTP(S), FTP, BitTorrent, and Metalink. aria2 can download a file from multiple sources/protocols and tries to utilize your maximum download bandwidth. It supports downloading a file from HTTP(S)/FTP and BitTorrent at the same time, while the data downloaded from HTTP(S)/FTP is uploaded to the BitTorrent swarm. Using Metalink's chunk checksums, aria2 automatically validates chunks of data while downloading a file like BitTorrent.

You can use the -x flag to specify the maximum number of connections per server (default: 1):

aria2c -x 16 [url] 

If the same file is available from multiple locations, you can choose to download from all of them. Use the -j flag to specify the maximum number of parallel downloads for every static URI (default: 5).

aria2c -j 5 [url] [url2]

Have a look at http://aria2.sourceforge.net/ for more information. For usage information, the man page is really descriptive and has a section on the bottom with usage examples. An online version can be found at http://aria2.sourceforge.net/manual/en/html/README.html.


u
user181677

wget cant download in multiple connections, instead you can try to user other program like aria2.


D
David Corp

use

aria2c -x 10 -i websites.txt >/dev/null 2>/dev/null &

in websites.txt put 1 url per line, example:

https://www.example.com/1.mp4
https://www.example.com/2.mp4
https://www.example.com/3.mp4
https://www.example.com/4.mp4
https://www.example.com/5.mp4

R
Rumble

try pcurl

http://sourceforge.net/projects/pcurl/

uses curl instead of wget, downloads in 10 segments in parallel.


p
pouya

They always say it depends but when it comes to mirroring a website The best exists httrack. It is super fast and easy to work. The only downside is it's so called support forum but you can find your way using official documentation. It has both GUI and CLI interface and it Supports cookies just read the docs This is the best.(Be cureful with this tool you can download the whole web on your harddrive)

httrack -c8 [url]

By default maximum number of simultaneous connections limited to 8 to avoid server overload


Really? The whole web?
e
ewwink

use xargs to make wget working in multiple file in parallel

#!/bin/bash

mywget()
{
    wget "$1"
}

export -f mywget

# run wget in parallel using 8 thread/connection
xargs -P 8 -n 1 -I {} bash -c "mywget '{}'" < list_urls.txt

Aria2 options, The right way working with file smaller than 20mb

aria2c -k 2M -x 10 -s 10 [url]

-k 2M split file into 2mb chunk

-k or --min-split-size has default value of 20mb, if you not set this option and file under 20mb it will only run in single connection no matter what value of -x or -s


m
mirhossein

You can use xargs

-P is the number of processes, for example, if set -P 4, four links will be downloaded at the same time, if set to -P 0, xargs will launch as many processes as possible and all of the links will be downloaded.

cat links.txt | xargs -P 4 -I{} wget {}

P
Pratik Balar

I'm using gnu parallel

cat listoflinks.txt | parallel --bar -j ${MAX_PARALLEL:-$(nproc)} wget -nv {}

cat will pipe a list of line separated URLs to parallel --bar flag will show parallel execution progress bar MAX_PARALLEL env var is for maximum no of parallel download, use it carefully, default here is current no of CPUs

tip: use --dry-run to see what will happen if you execute command. cat listoflinks.txt | parallel --dry-run --bar -j ${MAX_PARALLEL} wget -nv {}


P
Paul Price

make can be parallelised easily (e.g., make -j 4). For example, here's a simple Makefile I'm using to download files in parallel using wget:

BASE=http://www.somewhere.com/path/to
FILES=$(shell awk '{printf "%s.ext\n", $$1}' filelist.txt)
LOG=download.log

all: $(FILES)
    echo $(FILES)

%.ext:
    wget -N -a $(LOG) $(BASE)/$@

.PHONY: all
default: all

m
mgutt

Consider using Regular Expressions or FTP Globbing. By that you could start wget multiple times with different groups of filename starting characters depending on their frequency of occurrence.

This is for example how I sync a folder between two NAS:

wget --recursive --level 0 --no-host-directories --cut-dirs=2 --no-verbose --timestamping --backups=0 --bind-address=10.0.0.10 --user=<ftp_user> --password=<ftp_password> "ftp://10.0.0.100/foo/bar/[0-9a-hA-H]*" --directory-prefix=/volume1/foo &
wget --recursive --level 0 --no-host-directories --cut-dirs=2 --no-verbose --timestamping --backups=0 --bind-address=10.0.0.11 --user=<ftp_user> --password=<ftp_password> "ftp://10.0.0.100/foo/bar/[!0-9a-hA-H]*" --directory-prefix=/volume1/foo &

The first wget syncs all files/folders starting with 0, 1, 2... F, G, H and the second thread syncs everything else.

This was the easiest way to sync between a NAS with one 10G ethernet port (10.0.0.100) and a NAS with two 1G ethernet ports (10.0.0.10 and 10.0.0.11). I bound the two wget threads through --bind-address to the different ethernet ports and called them parallel by putting & at the end of each line. By that I was able to copy huge files with 2x 100 MB/s = 200 MB/s in total.


E
Everest Ok

Call Wget for each link and set it to run in background.

I tried this Python code

with open('links.txt', 'r')as f1:      # Opens links.txt file with read mode
  list_1 = f1.read().splitlines()      # Get every line in links.txt
for i in list_1:                       # Iteration over each link
  !wget "$i" -bq                       # Call wget with background mode

Parameters :

      b - Run in Background
      q - Quiet mode (No Output)