Disclaimer¶

Aria2c download files saved in a text file 5) Limit download bandwidth speed. By default, aria2 uses the maximum bandwidth to download files. This can result to degraded performance if you intend to upload or download files using other applications. Aria2 Download Manager through Entware TeHashX. 18 Comments Aria2 is a file sharing program. When you run a torrent, its data will be made available to others by means of upload.

This program comes with no warranty.You must use this program at your own risk.

Introduction¶

aria2 is a utility for downloading files. The supported protocols areHTTP(S), FTP, SFTP, BitTorrent, and Metalink. aria2 can download afile from multiple sources/protocols and tries to utilize your maximumdownload bandwidth. It supports downloading a file fromHTTP(S)/FTP/SFTP and BitTorrent at the same time, while the datadownloaded from HTTP(S)/FTP/SFTP is uploaded to the BitTorrentswarm. Using Metalink's chunk checksums, aria2 automatically validateschunks of data while downloading a file like BitTorrent.

The project page is located at https://aria2.github.io/.

See aria2 Online Manual (Russian translation, Portuguesetranslation) to learnhow to use aria2.

Features¶

Here is a list of features:

• Command-line interface
• Download files through HTTP(S)/FTP/SFTP/BitTorrent
• Segmented downloading
• Metalink version 4 (RFC 5854) support(HTTP/FTP/SFTP/BitTorrent)
• Metalink version 3.0 support(HTTP/FTP/SFTP/BitTorrent)
• Metalink/HTTP (RFC 6249) support
• HTTP/1.1 implementation
• HTTP Proxy support
• HTTP BASIC authentication support
• HTTP Proxy authentication support
• Well-known environment variables for proxy: http_proxy,https_proxy, ftp_proxy, all_proxy and no_proxy
• HTTP gzip, deflate content encoding support
• Verify peer using given trusted CA certificate in HTTPS
• Client certificate authentication in HTTPS
• Chunked transfer encoding support
• Load Cookies from file using the Firefox3 format, Chromium/Google Chromeand the Mozilla/Firefox(1.x/2.x)/Netscape format.
• Save Cookies in the Mozilla/Firefox (1.x/2.x)/Netscape format.
• Custom HTTP Header support
• Persistent Connections support
• FTP/SFTP through HTTP Proxy
• Download/Upload speed throttling
• BitTorrent extensions: Fast extension, DHT, PEX, MSE/PSE,Multi-Tracker, UDP tracker
• BitTorrent WEB-Seeding.aria2 requests chunks more than piece size to reduce the requestoverhead. It also supports pipelined requests with piece size.
• BitTorrent Local Peer Discovery
• Rename/change the directory structure of BitTorrent downloadscompletely
• JSON-RPC (over HTTP and WebSocket)/XML-RPC interface
• Run as a daemon process
• Selective download in multi-file torrent/Metalink
• Chunk checksum validation in Metalink
• Can disable segmented downloading in Metalink
• Netrc support
• Configuration file support
• Download URIs found in a text file or stdin and the destinationdirectory and output file name can be specified optionally
• Parameterized URI support
• IPv6 support with Happy Eyeballs
• Disk cache to reduce disk activity

Versioning and release schedule¶

We use 3 numbers for aria2 version: MAJOR.MINOR.PATCH. We will shipMINOR update on 15th of every month. We may skip a release if we haveno changes since the last release. The feature and documentationfreeze happens 10 days before the release day (5th day of the month)for translation teams. We will raise an issue about the upcomingrelease around that day.

We may release PATCH releases between regular releases if we havesecurity issues.

MAJOR version will stay at 1 for the time being.

How to get source code¶

We maintain the source code at Github:https://github.com/aria2/aria2

To get the latest source code, run following command:

This will create aria2 directory in your current directory and sourcefiles are stored there.

Dependency¶

Note

libxml2 has precedence over Expat if both libraries are installed.If you prefer Expat, run configure with --without-libxml2.

Note

On Apple OSX the OS-level SSL/TLS support will be preferred. Henceneither GnuTLS nor OpenSSL are required on that platform. If you'dlike to disable this behavior, run configure with--without-appletls.

GnuTLS has precedence over OpenSSL if both libraries are installed.If you prefer OpenSSL, run configure with --without-gnutls--with-openssl.

On Windows there is SSL implementation available that is based onthe native Windows SSL capabilities (Schannel) and it will bepreferred. Hence neither GnuTLS nor OpenSSL are required on thatplatform. If you'd like to disable this behavior, run configurewith --without-wintls.

Note

On Apple OSX the OS-level checksum support will be preferred,unless aria2 is configured with --without-appletls.

libnettle has precedence over libgcrypt if both libraries areinstalled. If you prefer libgcrypt, run configure with--without-libnettle--with-libgcrypt. If OpenSSL is selected overGnuTLS, neither libnettle nor libgcrypt will be used.

If none of the optional dependencies are installed, an internalimplementation that only supports md5 and sha1 will be used.

On Windows there is SSL implementation available that is based onthe native Windows capabilities and it will be preferred, unlessaria2 is configured with --without-wintls.

A user can have one of the following configurations for SSL and cryptolibraries:

• OpenSSL
• GnuTLS + libgcrypt
• GnuTLS + libnettle
• Apple TLS (OSX only)
• Windows TLS (Windows only)

You can disable BitTorrent and Metalink support by providing--disable-bittorrent and --disable-metalink to the configurescript respectively.

In order to enable async DNS support, you need c-ares.

• c-ares: http://c-ares.haxx.se/

How to build¶

aria2 is primarily written in C++. Initially it was written based onC++98/C++03 standard features. We are now migrating aria2 to C++11standard. The current source code requires C++11 aware compiler. Forwell-known compilers, such as g++ and clang, the -std=c++11 or-std=c++0x flag must be supported.

In order to build aria2 from the source package, you need followingdevelopment packages (package name may vary depending on thedistribution you use):

• libgnutls-dev (Required for HTTPS, BitTorrent, Checksum support)
• nettle-dev (Required for BitTorrent, Checksum support)
• libgmp-dev (Required for BitTorrent)
• libssh2-1-dev (Required for SFTP support)
• libc-ares-dev (Required for async DNS support)
• libxml2-dev (Required for Metalink support)
• zlib1g-dev (Required for gzip, deflate decoding support in HTTP)
• libsqlite3-dev (Required for Firefox3/Chromium cookie support)
• pkg-config (Required to detect installed libraries)

You can use libgcrypt-dev instead of nettle-dev and libgmp-dev:

• libgpg-error-dev (Required for BitTorrent, Checksum support)
• libgcrypt-dev (Required for BitTorrent, Checksum support)

You can use libssl-dev instead oflibgnutls-dev, nettle-dev, libgmp-dev, libgpg-error-dev and libgcrypt-dev:

• libssl-dev (Required for HTTPS, BitTorrent, Checksum support)

You can use libexpat1-dev instead of libxml2-dev:

• libexpat1-dev (Required for Metalink support)

On Fedora you need the following packages: gcc, gcc-c++, kernel-devel,libgcrypt-devel, libxml2-devel, openssl-devel, gettext-devel, cppunit

If you downloaded source code from git repository, you have to installfollowing packages to get autoconf macros:

• libxml2-dev
• libcppunit-dev
• autoconf
• automake
• autotools-dev
• autopoint
• libtool

And run following command to generate configure script and other filesnecessary to build the program:

Also you need Sphinx to build man page.

If you are building aria2 for Mac OS X, take a look atthe makerelease-osx.mk GNU Make makefile.

The quickest way to build aria2 is first run configure script:

To build statically linked aria2, use ARIA2_STATIC=yescommand-line option:

After configuration is done, run make to compile the program:

See Cross-compiling Windows binary to create a Windows binary.See Cross-compiling Android binary to create an Android binary.

The configure script checks available libraries and enables as manyfeatures as possible except for experimental features not enabled bydefault.

Since 1.1.0, aria2 checks the certificate of HTTPS servers by default.If you build with OpenSSL or the recent version of GnuTLS which hasgnutls_certificate_set_x509_system_trust() function and thelibrary is properly configured to locate the system-wide CAcertificates store, aria2 will automatically load those certificatesat the startup. If it is not the case, I recommend to supply the pathto the CA bundle file. For example, in Debian the path to CA bundlefile is '/etc/ssl/certs/ca-certificates.crt' (in ca-certificatespackage). This may vary depending on your distribution. You can giveit to configure script using --with-ca-bundleoption:

Without --with-ca-bundle option, you will encounter the error whenaccessing HTTPS servers because the certificate cannot be verifiedwithout CA bundle. In such case, you can specify the CA bundle fileusing aria2's --ca-certificate option. If you don't have CA bundlefile installed, then the last resort is disable the certificatevalidation using --check-certificate=false.

Using the native OSX (AppleTLS) and/or Windows (WinTLS) implementationwill automatically use the system certificate store, so--with-ca-bundle is not necessary and will be ignored when usingthese implementations.

By default, the bash_completion file named aria2c is installed tothe directory $prefix/share/doc/aria2/bash_completion. To changethe install directory of the file, use --with-bashcompletiondiroption.

After a make the executable is located at src/aria2c.

aria2 uses CppUnit for automated unit testing. To run the unit test:

Cross-compiling Windows binary¶

In this section, we describe how to build a Windows binary using amingw-w64 (http://mingw-w64.org/doku.php) cross-compiler on DebianLinux. The MinGW (http://www.mingw.org/) may not be able to buildaria2.

The easiest way to build Windows binary is use Dockerfile.mingw. SeeDockerfile.mingw how to build binary. If you cannot use Dockerfile,then continue to read following paragraphs.

Basically, after compiling and installing depended libraries, you cando cross-compile just passing appropriate --host option andspecifying CPPFLAGS, LDFLAGS and PKG_CONFIG_LIBDIRvariables to configure. For convenience and lowering our owndevelopment cost, we provide easier way to configure the buildsettings.

mingw-config script is a configure script wrapper for mingw-w64.We use it to create official Windows build. This script assumesfollowing libraries have been built for cross-compile:

• c-ares
• expat
• sqlite3
• zlib
• libssh2
• cppunit

Some environment variables can be adjusted to change build settings:

HOST

cross-compile to build programs to run on HOST. It defaults toi686-w64-mingw32. To build 64bit binary, specifyx86_64-w64-mingw32.

PREFIX

Prefix to the directory where dependent libraries are installed. Itdefaults to /usr/local/$HOST. -I$PREFIX/include will beadded to CPPFLAGS. -L$PREFIX/lib will be added toLDFLAGS. $PREFIX/lib/pkgconfig will be set toPKG_CONFIG_LIBDIR.

For example, to build 64bit binary do this:

If you want libaria2 dll with --enable-libaria2, then don't useARIA2_STATIC=yes and prepare the DLL version of externallibraries.

Cross-compiling Android binary¶

In this section, we describe how to build Android binary using AndroidNDK cross-compiler on Debian Linux.

At the time of this writing, Android NDK r20 should compile aria2without errors.

android-config script is a configure script wrapper for Androidbuild. We use it to create official Android build. This scriptassumes the following libraries have been built for cross-compile:

• c-ares
• openssl
• expat
• zlib
• libssh2

When building the above libraries, make sure that disable sharedlibrary and enable only static library. We are going to link thoselibraries statically.

android-config assumes that $ANDROID_HOME and $NDKenvironment variables are defined.

We currently use Android NDK r20. $NDK should point to thedirectory to Anroid NDK. The build tools will be found under$NDK/toolchains/llvm/prebuilt/linux-x86_64/bin/.

All the dependent libraries must be installed under$ANDROID_HOME/usr/local.

After android-config, run make to compile sources.

Building documentation¶

Sphinx is used to build thedocumentation. aria2 man pages will be build when you run make ifthey are not up-to-date. You can also build HTML version of aria2 manpage by makehtml. The HTML version manual is also available atonline (Russiantranslation, Portuguesetranslation).

BitTorrent¶

About file names¶

The file name of the downloaded file is determined as follows:

single-file mode

If 'name' key is present in .torrent file, file name is the valueof 'name' key. Otherwise, file name is the base name of .torrentfile appended by '.file'. For example, .torrent file is'test.torrent', then file name is 'test.torrent.file'. Thedirectory to store the downloaded file can be specified by -doption.

multi-file mode

The complete directory/file structure mentioned in .torrent fileis created. The directory to store the top directory ofdownloaded files can be specified by -d option.

Before download starts, a complete directory structure is created ifneeded. By default, aria2 opens at most 100 files mentioned in.torrent file, and directly writes to and reads from these files.The number of files to open simultaneously can be controlled by--bt-max-open-files option.

DHT¶

aria2 supports mainline compatible DHT. By default, the routing tablefor IPv4 DHT is saved to $XDG_CACHE_HOME/aria2/dht.dat and therouting table for IPv6 DHT is saved to$XDG_CACHE_HOME/aria2/dht6.dat unless files exist at$HOME/.aria2/dht.dat or $HOME/.aria2/dht6.dat. aria2 uses sameport number to listen on for both IPv4 and IPv6 DHT.

UDP tracker¶

UDP tracker support is enabled when IPv4 DHT is enabled. The portnumber of UDP tracker is shared with DHT. Use --dht-listen-portoption to change the port number.

Other things should be noted¶

• -o option is used to change the file name of .torrent file itself,not a file name of a file in .torrent file. For this purpose, use--index-out option instead.
• The port numbers that aria2 uses by default are 6881-6999 for TCPand UDP.
• aria2 doesn't configure port-forwarding automatically. Pleaseconfigure your router or firewall manually.
• The maximum number of peers is 55. This limit may be exceeded whendownload rate is low. This download rate can be adjusted using--bt-request-peer-speed-limit option.
• As of release 0.10.0, aria2 stops sending request message afterselective download completes.

Metalink¶

The current implementation supports HTTP(S)/FTP/SFTP/BitTorrent. Theother P2P protocols are ignored. Both Metalink4 (RFC 5854) andMetalink version 3.0 documents are supported.

For checksum verification, md5, sha-1, sha-224, sha-256, sha-384 andsha-512 are supported. If multiple hash algorithms are provided, aria2uses stronger one. If whole file checksum verification fails, aria2doesn't retry the download and just exits with non-zero return code.

The supported user preferences are version, language, location,protocol and os.

If chunk checksums are provided in Metalink file, aria2 automaticallyvalidates chunks of data during download. This behavior can be turnedoff by a command-line option.

If signature is included in a Metalink file, aria2 saves it as a fileafter the completion of the download. The file name is downloadfile name + '.sig'. If same file already exists, the signature file isnot saved.

In Metalink4, multi-file torrent could appear in metalink:metaurlelement. Since aria2 cannot download 2 same torrents at the sametime, aria2 groups files in metalink:file element which has sameBitTorrent metaurl and downloads them from a single BitTorrent swarm.This is basically multi-file torrent download with file selection, sothe adjacent files which is not in Metalink document but shares samepiece with selected file are also created.

If relative URI is specified in metalink:url or metalink:metaurlelement, aria2 uses the URI of Metalink file as base URI to resolvethe relative URI. If relative URI is found in Metalink file which isread from local disk, aria2 uses the value of --metalink-base-urioption as base URI. If this option is not specified, the relative URIwill be ignored.

Metalink/HTTP¶

The current implementation only uses rel=duplicate links only. aria2understands Digest header fields and check whether it matches thedigest value from other sources. If it differs, drop connection.aria2 also uses this digest value to perform checksum verificationafter download finished. aria2 recognizes geo value. To tell aria2which location you prefer, you can use --metalink-location option.

netrc¶

netrc support is enabled by default for HTTP(S)/FTP/SFTP. To disablenetrc support, specify -n command-line option. Your .netrc fileshould have correct permissions(600).

Aria 2 Download Manager Mac

WebSocket¶

The WebSocket server embedded in aria2 implements the specificationdefined in RFC 6455. The supported protocol version is 13.

libaria2¶

The libaria2 is a C++ library which offers aria2 functionality to theclient code. Currently, libaria2 is not built by default. To enablelibaria2, use --enable-libaria2 configure option. By default,only the shared library is built. To build static library, use--enable-static configure option as well. See libaria2documentation to know how to use API.

References¶

Aria2 Download Manager

• BitTorrent: UDP Tracker Protocol for BitTorrentand BitTorrent udp-tracker protocol specification.