ARIA2C(1)

NAME
aria2c - The ultra fast download utility

SYNOPSIS
aria2c [OPTIONS] [URL | TORRENT_FILE | METALINK_FILE]...

DESCRIPTION
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.

OPTIONS

  Basic Options

-d, --dir=DIR
    The directory to store the downloaded file.

-i, --input-file=FILE
    Downloads URIs found in FILE. You can specify multiple URIs for a single entity: separate URIs on a single line using the TAB character. Reads input from stdin when - is specified. The additional out and dir options can be specified after each line of URIs. This optional line must start with white space(s). See Input File subsection for details.

-l, --log=LOG
    The file name of the log file. If - is specified, log is written to stdout.

-j, --max-concurrent-downloads=N
    Set maximum number of parallel downloads for every static (HTTP/FTP) URL, torrent and metalink. See also -s and -C option. Default: 5

-V, --check-integrity[=true|false]
    Check file integrity by validating piece hashes. This option has effect only in BitTorrent and Metalink downloads with chunk checksums. Use this option to re-download a damaged portion of a file. Default: false

-c, --continue
    Continue downloading a partially downloaded file. Use this option to resume a download started by a web browser or another program which downloads files sequentially from the beginning. Currently this option is only applicable to HTTP(S)/FTP downloads.

-h, --help[=CATEGORY]
    Print usage and exit. The help messages are classified in several categories. For example, type "--help=http" for detailed explanation for the options related to HTTP. If no matching category is found, search option name using a given word in middle match and print the result. Available Values: basic, advanced, http, https, ftp, metalink, bittorrent, all Default: basic

  HTTP/FTP Options

--all-proxy=PROXY
    Use this proxy server for all protocols. You can override this setting and specify a proxy server for a particular protocol using --http-proxy, --https-proxy and --ftp-proxy options. This affects all URLs. The format of PROXY is [http://][USER:PASSWORD@]HOST[:PORT]

--connect-timeout=SEC
    Set the connect timeout in seconds to establish connection to HTTP/FTP/proxy server. After the connection is established, this option makes no effect and --timeout option is used instead. Default: 60

--dry-run[=true|false]
    If true is given, aria2 just checks whether the remote file is available and doesn't download data. This option has effect on HTTP/FTP download. BitTorrent downloads are canceled if true is specified. Default: false

--lowest-speed-limit=SPEED
    Close connection if download speed is lower than or equal to this value(bytes per sec). 0 means aria2 does not have a lowest speed limit. You can append K or M(1K = 1024, 1M = 1024K). This option does not affect BitTorrent downloads. Default: 0

--max-file-not-found=NUM
    If aria2 receives `file not found' status from the remote HTTP/FTP servers NUM times without getting a single byte, then force the download to fail. Specify 0 to disable this option. This options is effective only when using HTTP/FTP servers. Default: 0

-m, --max-tries=N
    Set number of tries. 0 means unlimited. Default: 5

--no-proxy=DOMAINS
    Specify comma separated hostnames or domains where proxy should not be used.

-o, --out=FILE
    The file name of the downloaded file.

Note In Metalink or BitTorrent download you cannot specify file name. The file name specified here is only used when the URLs fed to aria2 are done by command line without -i, -Z option. For example: aria2c -o myfile.zip "http://mirror1/file.zip" "http://mirror2/file.zip"

--proxy-method=METHOD
    Set the method to use in proxy request. METHOD is either get or tunnel. HTTPS downloads always use tunnel regardless of this option. Default: get

-R, --remote-time[=true|false]
    Retrieve timestamp of the remote file from the remote HTTP/FTP server and if it is available, apply it to the local file. Default: false

--retry-wait=SEC
    Set the seconds to wait to retry after an error has occured. Specify a value between 0 and 60. Default: 5

--server-stat-of=FILE
    Specify the filename to which performance profile of the servers is saved. You can load saved data using --server-stat-if option. See Server Performance Profile subsection below for file format.

--server-stat-if=FILE
    Specify the filename to load performance profile of the servers. The loaded data will be used in some URI selector such as feedback. See also --uri-selector option. See Server Performance Profile subsection below for file format.

--server-stat-timeout=SEC
    Specifies timeout in seconds to invalidate performance profile of the servers since the last contact to them. Default: 86400 (24hours)

-s, --split=N
    Download a file using N connections. If more than N URLs are given, first N URLs are used and remaining URLs are used for backup. If less than N URLs are given, those URLs are used more than once so that N connections total are made simultaneously. Please see -j option too. Please note that in Metalink download, this option has no effect and use -C option instead. Default: 5

-t, --timeout=SEC
    Set timeout in seconds. Default: 60

--uri-selector=SELECTOR
    Specify URI selection algorithm. The possible values are inorder, feedback and adaptive. If inorder is given, URI is tried in the order appeared in the URI list. If feedback is given, aria2 uses download speed observed in the previous downloads and choose fastest server in the URI list. This also effectively skips dead mirrors. The observed download speed is a part of performance profile of servers mentioned in --server-stat-of and --server-stat-if options. If adaptive is given, selects one of the best mirrors for the first and reserved connections. For supplementary ones, it returns mirrors which has not been tested yet, and if each of them has already been tested, returns mirrors which has to be tested again. Otherwise, it doesn't select anymore mirrors. Like feedback, it uses a performance profile of servers. Default: feedback

  HTTP Specific Options

--ca-certificate=FILE
    Use the certificate authorities in FILE to verify the peers. The certificate file must be in PEM format and can contain multiple CA certificates. Use --check-certificate option to enable verification.

--certificate=FILE
    Use the client certificate in FILE. The certificate must be in PEM format. You may use --private-key option to specify the private key.

--check-certificate[=true|false]
    Verify the peer using certificates specified in --ca-certificate option. Default: true

--http-auth-challenge[=true|false]
    Send HTTP authorization header only when it is requested by the server. If false is set, then authorization header is always sent to the server. There is an exception: if username and password are embedded in URI, authorization header is always sent to the server regardless of this option. Default: false

--http-auth-scheme=SCHEME
    Set HTTP authentication scheme. Currently, basic is the only supported scheme. Default: basic

--http-user=USER
    Set HTTP user. This affects all URLs.

--http-passwd=PASSWD
    Set HTTP password. This affects all URLs.

--http-proxy=PROXY
    Use this proxy server for HTTP. See also --all-proxy option. This affects all URLs. The format of PROXY is [http://][USER:PASSWORD@]HOST[:PORT]

--https-proxy=PROXY
    Use this proxy server for HTTPS. See also --all-proxy option. This affects all URLs. The format of PROXY is [http://][USER:PASSWORD@]HOST[:PORT]

--private-key=FILE
    Use the private key in FILE. The private key must be decrypted and in PEM format. The behavior when encrypted one is given is undefined. See also --certificate option.

--referer=REFERER
    Set Referer. This affects all URLs.

--enable-http-keep-alive[=true|false]
    Enable HTTP/1.1 persistent connection. Default: true

--enable-http-pipelining[=true|false]
    Enable HTTP/1.1 pipelining. Default: false

--header=HEADER
    Append HEADER to HTTP request header. You can use this option repeatedly to specify more than one header: aria2c --header="X-A: b78" --header="X-B: 9J1" "http://host/file"

--load-cookies=FILE
    Load Cookies from FILE using the Firefox3 format (SQLite3) and the Mozilla/Firefox(1.x/2.x)/Netscape format.

Note If aria2 is built without libsqlite3, then it doesn't support Firefox3 cookie format.

--use-head[=true|false]
    Use HEAD method for the first request to the HTTP server. Default: true

-U, --user-agent=USER_AGENT
    Set user agent for HTTP(S) downloads.

  FTP Specific Options

--ftp-user=USER
    Set FTP user. This affects all URLs. Default: anonymous

--ftp-passwd=PASSWD
    Set FTP password. This affects all URLs. Default: ARIA2USER@

-p, --ftp-pasv[=true|false]
    Use the passive mode in FTP. If false is given, the active mode will be used. Default: true

--ftp-proxy=PROXY
    Use this proxy server for FTP. See also --all-proxy option. This affects all URLs. The format of PROXY is [http://][USER:PASSWORD@]HOST[:PORT]

--ftp-type=TYPE
    Set FTP transfer type. TYPE is either binary or ascii. Default: binary

--ftp-reuse-connection[=true|false]
    Reuse connection in FTP. Default: true

-n, --no-netrc
    Disables netrc support. netrc support is enabled by default.

  BitTorrent/Metalink Options

--select-file=INDEX...
    Set file to download by specifying its index. You can find the file index using the --show-files option. Multiple indexes can be specified by using ",", for example: 3,6. You can also use "-" to specify a range: 1-5. "," and "-" can be used together: 1-5,8,9. When used with the -M option, index may vary depending on the query (see --metalink-* options).

Note In multi file torrent, the adjacent files specified by this option may also be downloaded. This is by design, not a bug. A single piece may include several files or part of files, and aria2 writes the piece to the appropriate files.

-S, --show-files
    Print file listing of .torrent or .metalink file and exit. In case of .torrent file, additional information (infohash, piece length, etc) is also printed.

  BitTorrent Specific Options

--bt-external-ip=IPADDRESS
    Specify the external IP address to report to a BitTorrent tracker. Although this function is named "external", it can accept any kind of IP addresses. IPADDRESS must be a numeric IP address.

--bt-hash-check-seed[=true|false]
    If true is given, after hash check using --check-integrity option and file is complete, continue to seed file. If you want to check file and download it only when it is damaged or incomplete, set this option to false. This option has effect only on BitTorrent download. Default: true

--bt-max-open-files=NUM
    Specify maximum number of files to open in each BitTorrent download. Default: 100

--bt-max-peers=NUM
    Specify the maximum number of peers per torrent. 0 means unlimited. See also --bt-request-peer-speed-limit option. Default: 55

--bt-min-crypto-level=plain|arc4
    Set minimum level of encryption method. If several encryption methods are provided by a peer, aria2 chooses the lowest one which satisfies the given level. Default: plain

--bt-require-crypto=true|false
    If true is given, aria2 doesn't accept and establish connection with legacy BitTorrent handshake(\19BitTorrent protocol). Thus aria2 always uses Obfuscation handshake. Default: false

--bt-request-peer-speed-limit=SPEED
    If the whole download speed of every torrent is lower than SPEED, aria2 temporarily increases the number of peers to try for more download speed. Configuring this option with your preferred download speed can increase your download speed in some cases. You can append K or M(1K = 1024, 1M = 1024K). Default: 50K

--bt-seed-unverified[=true|false]
    Seed previously downloaded files without verifying piece hashes. Default: false

--bt-tracker-interval=SEC
    Set the interval in seconds between tracker requests. This completely overrides interval value and aria2 just uses this value and ignores the min interval and interval value in the response of tracker. If 0 is set, aria2 determines interval based on the response of tracker and the download progress. Default: 0

--dht-entry-point=HOST:PORT
    Set host and port as an entry point to DHT network.

--dht-file-path=PATH
    Change the DHT routing table file to PATH. Default: $HOME/.aria2/dht.dat

--dht-listen-port=PORT...
    Set UDP listening port for DHT. Multiple ports can be specified by using ",", for example: 6881,6885. You can also use "-" to specify a range: 6881-6999. "," and "-" can be used together. Default: 6881-6999

Note Make sure that the specified ports are open for incoming UDP traffic.

--enable-dht[=true|false]
    Enable DHT functionality. If a private flag is set in a torrent, aria2 doesn't use DHT for that download even if true is given. Default: false

--enable-peer-exchange[=true|false]
    Enable Peer Exchange extension. If a private flag is set in a torrent, this feature is disabled for that download even if true is given. Default: true

--follow-torrent=true|false|mem
    If true or mem is specified, when a file whose suffix is ".torrent" or content type is "application/x-bittorrent" is downloaded, aria2 parses it as a torrent file and downloads files mentioned in it. If mem is specified, a torrent file is not written to the disk, but is just kept in memory. If false is specified, the action mentioned above is not taken. Default: true

-O, --index-out=INDEX=PATH
    Set file path for file with index=INDEX. You can find the file index using the --show-files option. PATH is a relative path to the path specified in --dir option. You can use this option multiple times. Using this option, you can specify the output filenames of BitTorrent downloads.

--listen-port=PORT...
    Set TCP port number for BitTorrent downloads. Multiple ports can be specified by using ",", for example: 6881,6885. You can also use "-" to specify a range: 6881-6999. "," and "-" can be used together: 6881-6889,6999. Default: 6881-6999

Note Make sure that the specified ports are open for incoming TCP traffic.

--max-overall-upload-limit=SPEED
    Set max overall upload speed in bytes/sec. 0 means unrestricted. You can append K or M(1K = 1024, 1M = 1024K). To limit the upload speed per torrent, use --max-upload-limit option. Default: 0

-u, --max-upload-limit=SPEED
    Set max upload speed per each torrent in bytes/sec. 0 means unrestricted. You can append K or M(1K = 1024, 1M = 1024K). To limit the overall upload speed, use --max-overall-upload-limit option. Default: 0

--peer-id-prefix=PEERI_ID_PREFIX
    Specify the prefix of peer ID. The peer ID in BitTorrent is 20 byte length. If more than 20 bytes are specified, only first 20 bytes are used. If less than 20 bytes are specified, the random alphabet characters are added to make it's length 20 bytes. Default: -aria2-

--seed-ratio=RATIO
    Specify share ratio. Seed completed torrents until share ratio reaches RATIO. You are strongly encouraged to specify equals or more than 1.0 here. Specify 0.0 if you intend to do seeding regardless of share ratio. If --seed-time option is specified along with this option, seeding ends when at least one of the conditions is satisfied. Default: 1.0

--seed-time=MINUTES
    Specify seeding time in minutes. Also see the --seed-ratio option.

-T, --torrent-file=TORRENT_FILE
    The path to the .torrent file. You are not required to use this option because you can specify a torrent file without -T.

  Metalink Specific Options

--follow-metalink=true|false|mem
    If true or mem is specified, when a file whose suffix is ".metaink" or content type of "application/metalink+xml" is downloaded, aria2 parses it as a metalink file and downloads files mentioned in it. If mem is specified, a metalink file is not written to the disk, but is just kept in memory. If false is specified, the action mentioned above is not taken. Default: true

-M, --metalink-file=METALINK_FILE
    The file path to .metalink file. You are not required to use this option because you can specify a metalink file without -M.

-C, --metalink-servers=NUM_SERVERS
    The number of servers to connect to simultaneously. Some Metalinks regulate the number of servers to connect. aria2 strictly respects them. This means that if Metalink defines the maxconnections attribute lower than NUM_SERVERS, then aria2 uses the value of maxconnections attribute instead of NUM_SERVERS. See also -s and -j options. Default: 5

--metalink-language=LANGUAGE
    The language of the file to download.

--metalink-location=LOCATION[,...]
    The location of the preferred server. A comma-delimited list of locations is acceptable, for example, JP,US.

--metalink-os=OS
    The operating system of the file to download.

--metalink-version=VERSION
    The version of the file to download.

--metalink-preferred-protocol=PROTO
    Specify preferred protocol. The possible values are http, https, ftp and none. Specify none to disable this feature. Default: none

--metalink-enable-unique-protocol=true|false
    If true is given and several protocols are available for a mirror in a metalink file, aria2 uses one of them. Use --metalink-preferred-protocol option to specify the preference of protocol. Default: true

  Advanced Options

--allow-overwrite=true|false
    If false is given, aria2 doesn't download a file which already exists but the corresponding .aria2 file doesn't exist. In HTTP(S)/FTP download, if --auto-file-renaming=true then, file name will be renamed. See --auto-file-renaming for details. Default: false

--allow-piece-length-change=true|false
    If false is given, aria2 aborts download when a piece length is different from one in a control file. If true is given, you can proceed but some download progress will be lost. Default: false

--async-dns[=true|false]
    Enable asynchronous DNS. Default: true

--auto-file-renaming[=true|false]
    Rename file name if the same file already exists. This option works only in HTTP(S)/FTP download. The new file name has a dot and a number(1..9999) appended. Default: true

--auto-save-interval=SEC
    Save a control file(*.aria2) every SEC seconds. If 0 is given, a control file is not saved during download. aria2 saves a control file when it stops regardless of the value. The possible values are between 0 to 600. Default: 60

--conf-path=PATH
    Change the configuration file path to PATH. Default: $HOME/.aria2/aria2.conf

-D, --daemon
    Run as daemon.

--enable-direct-io[=true|false]
    Enable directI/O, which lowers cpu usage while allocating/checking files. Turn off if you encounter any error. Default: true

--enable-http-server[=true|false]
    Enable the built-in HTTP server. Currently, this is the experimental feature and it just provides the current download progress. Use your web browser(console-based ones, such as elinks, w3m, are recommended) to connect the server and see what's what. See also --http-server-listen-port option. Default: false

--event-poll=POLL
    Specify the method for polling events. The possible Values are epoll and select. If you use recent Linux that has epoll, then the default value is epoll. Otherwise, the default value is select.

--file-allocation=METHOD
    Specify file allocation method. METHOD is either none or prealloc. none doesn't pre-allocate file space. prealloc pre-allocates file space before download begins. This may take some time depending on the size of the file. If you are using newer file systems such as ext4 (with extents support), btrfs or xfs, falloc is your best choice. It allocates large(few GiB) files almost instantly. Don't use falloc with legacy file systems such as ext3 because it takes almost same time as prealloc and it blocks aria2 entirely until allocation finishes. falloc may not be available if your system doesn't have posix_fallocate() function. Default: prealloc

--log-level=LEVEL
    Set log level to output. LEVEL is either debug, info, notice, warn or error. Default: debug

--summary-interval=SEC
    Set interval in seconds to output download progress summary. Setting 0 suppresses the output. Default: 60

Note In multi file torrent downloads, the files adjacent forward to the specified files are also allocated if they share the same piece.

-Z, --force-sequential[=true|false]
    Fetch URIs in the command-line sequentially and download each URI in a separate session, like the usual command-line download utilities. Default: false

--http-server-listen-port=PORT
    Specify a port number for the built-in HTTP Server to listen to. See also --enable-http-server option. The possible Values are 1024-65535. Default: 6800

--max-overall-download-limit=SPEED
    Set max overall download speed in bytes/sec. 0 means unrestricted. You can append K or M(1K = 1024, 1M = 1024K). To limit the download speed per download, use --max-download-limit option. Default: 0

--max-download-limit=SPEED
    Set max download speed per each download in bytes/sec. 0 means unrestricted. You can append K or M(1K = 1024, 1M = 1024K). To limit the overall download speed, use --max-overall-download-limit option. Default: 0

--no-conf
    Disable loading aria2.conf file.

--no-file-allocation-limit=SIZE
    No file allocation is made for files whose size is smaller than SIZE. You can append K or M(1K = 1024, 1M = 1024K). Default: 5M

-P, --parameterized-uri[=true|false]
    Enable parameterized URI support. You can specify set of parts: http://{sv1,sv2,sv3}/foo.iso. Also you can specify numeric sequences with step counter: http://host/image[000-100:2].img. A step counter can be omitted. If all URIs do not point to the same file, such as the second example above, -Z option is required. Default: false

-q, --quiet[=true|false]
    Make aria2 quiet (no console output). Default: false

--realtime-chunk-checksum=true|false
    Validate chunk of data by calculating checksum while downloading a file if chunk checksums are provided. Default: true

--stop=SEC
    Stop application after SEC seconds has passed. If 0 is given, this feature is disabled. Default: 0

-v, --version
    Print the version number, copyright and the configuration information and exit.

  Options That Take An Optional Argument
The options that have its argument surrounded by square brackets([]) take an optional argument. Usually omiting the argument is evaluated to true. If you use short form of these options(such as -V) and give an argument, then the option name and its argument should be concatenated(e.g. -Vfalse). If any spaces are inserted between the option name and the argument, the argument will be treated as URI and usually this is not what you expect.

  URL, TORRENT_FILE, METALINK_FILE
You can specify multiple URLs in command-line. Unless you specify -Z option, all URLs must point to the same file or downloading will fail.

You can also specify arbitrary number of torrent files and metalink files stored on a local drive. Please note that they are always treated as a separate download.

You can specify both torrent file with -T option and URLs. By doing this, you can download a file from both torrent swarm and HTTP(S)/FTP server at the same time, while the data from HTTP(S)/FTP are uploaded to the torrent swarm. Note that only single file torrent can be integrated with HTTP(S)/FTP.

Note Make sure that URL is quoted with single(') or double(") quotation if it contains "&" or any characters that have special meaning in shell.

  Resuming Download
Usually, you can resume transfer by just issuing same command(aria2c URL) if the previous transfer is made by aria2.

If the previous transfer is made by a browser or wget like sequential download manager, then use -c option to continue the transfer(aria2c -c URL).

EXIT STATUS
Because aria2 can handle multiple downloads at once, it encounters lots of errors in a session. aria2 returns the following exit status based on the last error encountered.

0
    If all downloads are successful.

1
    If an unknown error occurs.

2
    If time out occurs.

3
    If a resource is not found.

4
    If aria2 sees the specfied number of "resource not found" error. See --max-file-not-found option).

5
    If a download aborts because download speed is too slow. See --lowest-speed-limit option)

6
    If network problem occurs.

7
    If there are unfinished downloads. This error is only reported if all finished downloads are successful and there are unfinished downloads in a queue when aria2 exits by pressing Ctrl-C by an user or sending TERM or INT signal.

Note An error occurred in a finished download will not be reported as exit status.

ENVIRONMENT
aria2 recognizes the following environment variables.

http_proxy [http://][USER:PASSWORD@]HOST[:PORT]
    Specify proxy server for use in HTTP. Overrides http-proxy value in configuration file. The command-line option --http-proxy overrides this value.

https_proxy [http://][USER:PASSWORD@]HOST[:PORT]
    Specify proxy server for use in HTTPS. Overrides https-proxy value in configuration file. The command-line option --https-proxy overrides this value.

ftp_proxy [http://][USER:PASSWORD@]HOST[:PORT]
    Specify proxy server for use in FTP. Overrides ftp-proxy value in configuration file. The command-line option --ftp-proxy overrides this value.

all_proxy [http://][USER:PASSWORD@]HOST[:PORT]
    Specify proxy server for use if no protocol-specific proxy is specified. Overrides all-proxy value in configuration file. The command-line option --all-proxy overrides this value.

no_proxy [DOMAIN,...]
    Specify comma-separated hostname or domains to which proxy should not be used. Overrides no-proxy value in configuration file. The command-line option --no-proxy overrides this value.

FILES

  aria2.conf
By default, aria2 parses $HOME/.aria2/aria2.conf as a configuraiton file. You can specify the path to configuration file using --conf-path option. If you don't want to use the configuraitonf file, use --no-conf option.

The configuration file is a text file and has 1 option per each line. In each line, you can specify name-value pair in the format: NAME=VALUE, where name is the long command-line option name without "--" prefix. You can use same syntax for the command-line option. The lines beginning "#" are treated as comments.

    # sample configuration file for aria2c
    listen-port=60000
    dht-listen-port=60000
    seed-ratio=1.0
    max-upload-limit=50K
    ftp-pasv=true

  dht.dat
By default, the routing table of DHT is saved to the path $HOME/.aria2/dht.dat.

  Control File
aria2 uses a control file to track the progress of a download. A control file is placed in the same directory as the downloading file and its filename is the filename of downloading file with ".aria2" appended. For example, if you are downloading file.zip, then the control file should be file.zip.aria2. (There is a exception for this naming convention. If you are downloading a multi torrent, its control file is the "top directory" name of the torrent with ".aria2" appended. The "top directory" name is a value of "name" key in "info" directory in a torrent file.)

Usually a control file is deleted once download completed. If aria2 decides that download cannot be resumed(for example, when downloading a file from a HTTP server which doesn't support resume), a control file is not created.

Normally if you lose a control file, you cannot resume download. But if you have a torrent or metalink with chunk checksums for the file, you can resume the download without a control file by giving -V option to aria2c in command-line.

  Input File
The input file can contain a list of URIs for aria2 to download. You can specify multiple URIs for a single entity: separate URIs on a single line using the TAB character.

Each line is treated as if it is provided in command-line argument. Therefore they are affected by -Z and -P options.

Additionally, the following options can be specified after each line of URIs. These optional lines must start with white space(s).

    • out

    • dir

    • select-file

    • index-out
These options have exactly same meaning of the ones in the command-line options, but it just applies to the URIs it belongs to.

For example, the content of uri.txt is

    http://server/file.iso http://mirror/file.iso
      dir=/iso_images
      out=file.img
    http://foo/bar
If aria2 is executed with -i uri.txt -d /tmp options, then file.iso is saved as /iso_images/file.img and it is downloaded from http://server/file.iso and http://mirror/file.iso. The file bar is downloaded from http://foo/bar and saved as /tmp/bar.

In some cases, out parameter has no effect. See note of --out option for the restrictions.

  Server Performance Profile
This section describes the format of server performance profile. The file is plain text and each line has several NAME=VALUE pair, delimited by comma. Currently following NAMEs are recognized:

host
    Hostname of the server. Required.

protocol
    Protocol for this profile, such as ftp, http. Required.

dl_speed
    The average download speed observed in the previous download in bytes per sec. Required.

sc_avg_speed
    The average download speed observed in the previous download in bytes per sec. This value is only updated if the download is done in single connection environment and only used by AdaptiveURISelector. Optional.

mc_avg_speed
    The average download speed observed in the previous download in bytes per sec. This value is only updated if the download is done in multi connection environment and only used by AdaptiveURISelector. Optional.

counter
    How many times the server is used. Currently this value is only used by AdaptiveURISelector. Optional.

last_updated
    Last contact time in GMT with this server, specified in the seconds from the Epoch. Required.

status
    ERROR is set when server cannot be reached or out-of-service or timeout occurred. Otherwise, OK is set.
Those fields must exist in one line. The order of the fields is not significant. You can put pairs other than the above; they are simply ignored.

An example follows:

    host=localhost, protocol=http, dl_speed=32000, last_updated=1222491640, status=OK
    host=localhost, protocol=ftp, dl_speed=0, last_updated=1222491632, status=ERROR

EXAMPLE

  HTTP/FTP Segmented Download

Download a file

        aria2c "http://host/file.zip"

    Note aria2 uses 5 connections to download 1 file by default.

Download a file using 1 connection

        aria2c -s1 "http://host/file.zip"

    Note aria2 uses 5 connections to download 1 file by default. -s1 limits the number of connections to just 1.

    Note To pause a download, press Ctrl-C. You can resume the transfer by running aria2c with the same argument in the same directory. You can change URLs as long as they are pointing to the same file.

Download a file from 2 different HTTP servers

        aria2c "http://host/file.zip" "http://mirror/file.zip"

Download a file from HTTP and FTP servers

        aria2c "http://host1/file.zip" "ftp://host2/file.zip"

Download files listed in a text file concurrently

        aria2c -ifiles.txt -j2

    Note -j option specifies the number of parallel downloads.

Using proxy
    For HTTP:

        aria2c --http-proxy="http://proxy:8080" "http://host/file"
    For FTP:

        aria2c --ftp-proxy="http://proxy:8080" "ftp://host/file"

    Note See --http-proxy, --https-proxy, --ftp-proxy and --all-proxy for details. You can specify proxy in the environment variables. See ENVIRONMENT section.

Proxy with authorization

        aria2c --http-proxy="http://username:password@proxy:8080" "http://host/file"

  Metalink Download

Download files with remote Metalink

        aria2c --follow-metalink=mem "http://host/file.metalink"

Download using a local metalink file

        aria2c -p --lowest-speed-limit=4000 file.metalink

    Note To pause a download, press Ctrl-C. You can resume the transfer by running aria2c with the same argument in the same directory.

Download several local metalink files

        aria2c -j2 file1.metalink file2.metalink

Download only selected files using index

        aria2c --select-file=1-4,8 file.metalink

    Note The index is printed to the console using -S option.

Download a file using a local .metalink file with user preference

        aria2c --metalink-location=JP,US --metalink-version=1.1 --metalink-language=en-US file.metalink

  BitTorrent Download

Download files from remote BitTorrent file

        aria2c --follow-torrent=mem "http://host/file.torrent"

Download using a local torrent file

        aria2c --max-upload-limit=40K file.torrent

    Note --max-upload-limit specifies the max of upload rate.

    Note To pause a download, press Ctrl-C. You can resume the transfer by run aria2c with the same argument in the same directory.

Download 2 torrents

        aria2c -j2 file1.torrent file2.torrent

Download a file using torrent and HTTP/FTP server

        aria2c -Ttest.torrent "http://host1/file" "ftp://host2/file"

    Note Downloading multi file torrent with HTTP/FTP is not supported.

Download only selected files using index(usually called "selectable download")

        aria2c --select-file=1-4,8 file.torrent

    Note The index is printed to the console using -S option.

Specify output filename
    To specify output filename for BitTorrent downloads, you need to know the index of file in torrent file using -S option. For example, the output looks like this:

        idx|path/length
        ===+======================
          1|dist/base-2.6.18.iso
           |99.9MiB
        ---+----------------------
          2|dist/driver-2.6.18.iso
           |169.0MiB
        ---+----------------------
    To save dist/base-2.6.18.iso in /tmp/mydir/base.iso and dist/driver-2.6.18.iso in /tmp/dir/driver.iso, use the following command:

        aria2c --dir=/tmp --index-out=1=mydir/base.iso --index-out=2=dir/driver.iso file.torrent

Change the listening port for incoming peer

        aria2c --listen-port=7000-7001,8000 file.torrent

    Note Since aria2 doesn't configure firewall or router for port forwarding, it's up to you to do it manually.

Specify the condition to stop program after torrent download finished

        aria2c --seed-time=120 --seed-ratio=1.0 file.torrent

    Note In the above example, the program exits when the 120 minutes has elapsed since download completed or seed ratio reaches 1.0.

Throttle upload speed

        aria2c --max-upload-limit=100K file.torrent

Enable DHT

        aria2c --enable-dht --dht-listen-port=6881 file.torrent

    Note DHT uses udp port. Since aria2 doesn't configure firewall or router for port forwarding, it's up to you to do it manually.

  More advanced HTTP features

Load cookies

        aria2c --load-cookies=cookies.txt "http://host/file.zip"

    Note You can use Firefox/Mozilla's cookie file without modification.

Resume download started by web browsers or another programs

        aria2c -c -s2 "http://host/partiallydownloadedfile.zip"

Client certificate authorization for SSL/TLS

        aria2c --certificate=/path/to/mycert.pem --private-key=/path/to/mykey.pem https://host/file

    Note The file specified in --private-key must be decrypted. The behavior when encrypted one is given is undefined.

Verify peer in SSL/TLS using given CA certificates

        aria2c --ca-certificate=/path/to/ca-certificates.crt --check-certificate https://host/file

  And more advanced features

Throttle download speed

        aria2c --max-download-limit=100K file.metalink

Repair a damaged download using -V option

        aria2c -V file.metalink

    Note This option is only available used with BitTorrent or metalink with chunk checksums.

Drop connection if download speed is lower than specified value

        aria2c --lowest-speed-limit=10K file.metalink

Parameterized URI support
    You can specify set of parts:

        aria2c -P "http://{host1,host2,host3}/file.iso"
    You can specify numeric sequence:

        aria2c -Z -P "http://host/image[000-100].png"

    Note -Z option is required if the all URIs don't point to the same file, such as the above example.

    You can specify step counter:

        aria2c -Z -P "http://host/image[A-Z:2].png"

Parallel downloads of arbitrary number of URL,metalink,torrent

        aria2c -j3 -Z "http://host/file1" file2.torrent file3.metalink

BitTorrent Encryption
    Encrypt whole payload using ARC4:

        aria2c --bt-min-crypto-level=arc4 --bt-require-crypto=true file.torrent

SEE ALSO
Project Web Site: http://aria2.sourceforge.net/

aria2 Wiki: http://apps.sourceforge.net/trac/aria2/wiki

Metalink Homepage: http://www.metalinker.org/

COPYRIGHT
Copyright © 2006, 2009 Tatsuhiro Tsujikawa

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

In addition, as a special exception, the copyright holders give permission to link the code of portions of this program with the OpenSSL library under certain conditions as described in each individual source file, and distribute linked combinations including the two. You must obey the GNU General Public License in all respects for all of the code used other than OpenSSL. If you modify file(s) with this exception, you may extend this exception to your version of the file(s), but you are not obligated to do so. If you do not wish to do so, delete this exception statement from your version. If you delete this exception statement from all source files in the program, then also delete it here.