$ ./configure $ make
This program comes with no warranty. You must use this program at your own risk.
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.
Here is a list of features.
Command-line interface
Download files through HTTP(S)/FTP/BitTorrent
Segmented downloading
Metalink version 3.0 support(HTTP/FTP/BitTorrent)
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 and the Mozilla/Firefox (1.x/2.x)/Netscape format.
Custom HTTP Header support
Persistent Connections support
FTP through HTTP Proxy
Download/Upload speed throttling
BitTorrent extensions: Fast extension, DHT, PEX, MSE/PSE, Multi-Tracker
BitTorrent WEB-Seeding (single-file torrent only)
Rename/change the directory structure of BitTorrent downloads completely
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 destination directory and output filename can be specified optionally
Parameterized URI support
| features | dependency |
|---|---|
| HTTPS | GnuTLS or OpenSSL |
| BitTorrent | GnuTLS+Libgcrypt or OpenSSL |
| Metalink | libxml2 or Expat. |
| Checksum | GnuTLS+Libgcrypt or OpenSSL |
| gzip, deflate in HTTP | zlib |
| Async DNS | C-Ares |
| Firefox3 cookie | libsqlite3 |
GNU TLS has precedence over OpenSSL if both libraries are installed. If you prefer OpenSSL, run configure with --without-gnutls.
libxml2 has precedence over Expat if both libraries are installed. If you prefer Expat, run configure with --without-libxml2.
You can disable BitTorrent, Metalink support by providing --disable-bittorrent, --disable-metalink respectively to configure script.
In order to enable async DNS support, you need c-ares.
In order to build aria2 from the source package, you need following development packages(package name may vary depending on the distribution you use):
libgnutls-dev (Required for HTTPS, BitTorrent, Checksum support)
libgpg-error-dev (Required for BitTorrent, Checksum support)
libgcrypt-dev (Required for BitTorrent, Checksum support)
libc-ares-dev (Required for async DNS support)
libxml2-dev (Required for Metalink support)
libz1g-dev (Required for gzip, deflate decoding support in HTTP)
libsqlite3-dev (Required for Firefox3 cookie support)
You can use libssl-dev instead of libgnutls-dev,libgpg-error-dev,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)
The quickest way to build aria2 is just type following commands:
$ ./configure $ make
The configure script checks available libraries and enables the features as much as possible because all the features are enabled by default.
Since 1.1.0, aria2 checks the certificate of HTTPS servers by default. If you build with HTTPS support, I recommend to supply the path to the CA bundle file. For example, in Debian the path to CA bundle file is /etc/ssl/certs/ca-certificates.crt (in ca-certificates package). This may vary depending on your distribution. You can give it to configure script using --with-ca-bundle option:
$ ./configure --with-ca-bundle='/etc/ssl/certs/ca-certificates.crt' $ make
Without --with-ca-bundle option, you will encounter the error when accessing HTTPS servers because the certificate cannot be verified without CA bundle. In such case, you can specify the CA bundle file using aria2's --ca-certificate option. If you don't have CA bundle file installed, then the last resort is disable the certificate validation using --check-certificate=false.
The executable is aria2c in src directory.
aria2 uses CppUnit for automated unit testing. To run the unit test:
$ make check
The filename of the downloaded file is determined as follows:
If "name" key is present in .torrent file, filename is the value of "name" key. Otherwise, filename is the basename of .torrent file appended by ".file". For example, .torrent file is "test.torrrent", then filename is "test.torrent.file". The directory to store the downloaded file can be specified by -d option.
The complete directory/file structure mentioned in .torrent file is created. The directory to store the top directory of downloaded files can be specified by -d option.
Before download starts, a complete directory structure is created if needed. 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.
As of release 0.13.0, aria2 supports DHT. By default, the routing table is saved to $HOME/.aria2/dht.dat.
-o option is used to change the filename of .torrent file itself, not a filename of a file in .torrent file.
The port numbers that aria2 uses by default are 6881-6999 for TCP and UDP.
aria2 doesn't configure port-forwarding automatically. Please configure your router or firewall manually.
The maximum number of peers is 55. This limit may be exceeded when download 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 after selective download completes.
The current implementation supports HTTP(S)/FTP/BitTorrent. The other P2P protocols are ignored.
For checksum verification, MD5, SHA1, and SHA256 are supported. If multiple hash algorithms are provided, aria2 uses SHA1. If whole file checksum verification fails, aria2 doesn'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 automatically validates chunks of data during download. This behavior can be turned off by a command-line option.
If signature is included in a Metalink file, aria2 saves it as a file after the completion of the download. The filename is download filename + ".sig". If same file already exists, the signature file is not saved.
netrc support is enabled by default for HTTP(S)/FTP. To disable netrc support, specify -n command-line option. Your .netrc file should have correct permissions(600).