ARIA2C(1) Manual Page

The directory to store the downloaded 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. Additionally, options can be specified after each line of URI. This optional line must start with one or more white spaces and have one option per single line. See Input File subsection for details.

The file name of the log file. If - is specified, log is written to stdout. If empty string("") is specified, log is not written to file.

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

Check file integrity by validating piece hashes or a hash of entire file. This option has effect only in BitTorrent and Metalink downloads with checksums. If piece hashes are provided, this option can detect damaged portions of a file and re-download them. If a hash of entire file is provided, hash check is only done when file has benn already download. This is determined by file length. If hash check fails, file is re-downloaded from scratch. If both piece hashes and a hash of entire file are provided, only piece hashes are used. Default: false

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.

The help messages are classified with tags. A tag starts with "#". For example, type "--help=#http" to get the usage for the options tagged with "#http". If non-tag word is given, print the usage for the options whose name includes that word. Available Values: #basic, #advanced, #http, #https, #ftp, #metalink, #bittorrent, #cookie, #hook, #file, #rpc, #experimental, #all Default: #basic

Use this proxy server for all protocols. To erase previously defined proxy, use "". 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 URIs. The format of PROXY is [http://][USER:PASSWORD@]HOST[:PORT]. See also ENVIRONMENT section.

Set password for --all-proxy option.

Set user for --all-proxy option.

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

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

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

The maximum number of connections to one server for each download. Default: 1

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

Set number of tries. 0 means unlimited. See also --retry-wait. Default: 5

aria2 does not split less than 2*SIZE byte range. For example, let’s consider downloading 20MiB file. If SIZE is 10M, aria2 can split file into 2 range [0-10MiB) and [10MiB-20MiB) and download it using 2 sources(if --split >= 2, of course). If SIZE is 15M, since 2*15M > 20MiB, aria2 does not split file and download it using 1 source. You can append K or M(1K = 1024, 1M = 1024K). Possible Values: 1M-1024M Default: 20M

Disables netrc support. netrc support is enabled by default.

Specify comma separated hostnames, domains and network address with or without CIDR block where proxy should not be used.

The file name of the downloaded file. When -Z option is used, this option is ignored.

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

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

Reuse already used URIs if no unused URIs are left. Default: true

Set the seconds to wait between retries. With SEC > 0, aria2 will retry download when the HTTP server returns 503 response. Default: 0

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.

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.

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

Download a file using N connections. If more than N URIs are given, first N URIs are used and remaining URIs are used for backup. If less than N URIs are given, those URIs are used more than once so that N connections total are made simultaneously. The number of connections to the same host is restricted by --max-connection-per-server option. Please see -j and --min-split-size option too. Please note that in Metalink download, this option has no effect and use -C option instead. Default: 5

Set timeout in seconds. Default: 60

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

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.

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

Verify the peer using certificates specified in --ca-certificate option. Default: true

Send "Accept: deflate, gzip" request header and inflate response if remote server responds with "Content-Encoding: gzip" or "Content-Encoding: deflate". Default: 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

Send Cache-Control: no-cache and Pragma: no-cache header to avoid cached content. If false is given, these headers are not sent and you can add Cache-Control header with a directive you like using --header option. Default: true

Set HTTP user. This affects all URIs.

Set HTTP password. This affects all URIs.

Use this proxy server for HTTP. To erase previously defined proxy, use "". See also --all-proxy option. This affects all URIs. The format of PROXY is [http://][USER:PASSWORD@]HOST[:PORT]

Set password for --http-proxy option.

Set user for --http-proxy option.

Use this proxy server for HTTPS. To erase previously defined proxy, use "". See also --all-proxy option. This affects all URIs. The format of PROXY is [http://][USER:PASSWORD@]HOST[:PORT]

Set password for --https-proxy option.

Set user for --https-proxy option.

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.

Set Referer. This affects all URIs.

Enable HTTP/1.1 persistent connection. Default: true

Enable HTTP/1.1 pipelining. Default: false

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 from FILE using the Firefox3 format (SQLite3), Chromium/Google Chrome (SQLite3) and the Mozilla/Firefox(1.x/2.x)/Netscape format.

Save Cookies to FILE in Mozilla/Firefox(1.x/2.x)/ Netscape format. If FILE already exists, it is overwritten. Session Cookies are also saved and their expiry values are treated as 0. Possible Values: /path/to/file

Use HEAD method for the first request to the HTTP server. Default: false

Set user agent for HTTP(S) downloads. Default: aria2/$VERSION, $VERSION is replaced by package version.

Set FTP user. This affects all URIs. Default: anonymous

Set FTP password. This affects all URIs. If user name is embedded but password is missing in URI, aria2 tries to resolve password using .netrc. If password is found in .netrc, then use it as password. If not, use the password specified in this option. Default: ARIA2USER@

Use the passive mode in FTP. If false is given, the active mode will be used. Default: true

Use this proxy server for FTP. To erase previously defined proxy, use "". See also --all-proxy option. This affects all URIs. The format of PROXY is [http://][USER:PASSWORD@]HOST[:PORT]

Set password for --ftp-proxy option.

Set user for --ftp-proxy option.

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

Reuse connection in FTP. Default: true

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).

Print file listing of .torrent, .meta4 and .metalink file and exit. In case of .torrent file, additional information (infohash, piece length, etc) is also printed.

Enable Local Peer Discovery. If a private flag is set in a torrent, aria2 doesn’t use this feature for that download even if true is given. Default: false

Comma separated list of BitTorrent tracker’s announce URI to remove. You can use special value "*" which matches all URIs, thus removes all announce URIs. When specifying "*" in shell command-line, don’t forget to escape or quote it. See also --bt-tracker option.

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.

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

Use given interface for Local Peer Discovery. If this option is not specified, the default interface is chosen. You can specify interface name and IP address. Possible Values: interface, IP addres

Specify maximum number of files to open in each BitTorrent download. Default: 100

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

Download metadata only. The file(s) described in metadata will not be downloaded. This option has effect only when BitTorrent Magnet URI is used. See also --bt-save-metadata option. Default: false

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

Try to download first and last pieces of each file first. This is useful for previewing files. The argument can contain 2 keywords: head and tail. To include both keywords, they must be separated by comma. These keywords can take one parameter, SIZE. For example, if head=SIZE is specified, pieces in the range of first SIZE bytes of each file get higher priority. tail=SIZE means the range of last SIZE bytes of each file. SIZE can include K or M(1K = 1024, 1M = 1024K). If SIZE is omitted, SIZE=1M is used.

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

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

Save metadata as .torrent file. This option has effect only when BitTorrent Magnet URI is used. The filename is hex encoded info hash with suffix .torrent. The directory to be saved is the same directory where download file is saved. If the same file already exists, metadata is not saved. See also --bt-metadata-only option. Default: false

Seed previously downloaded files without verifying piece hashes. Default: false

Stop BitTorrent download if download speed is 0 in consecutive SEC seconds. If 0 is given, this feature is disabled. Default: 0

Comma separated list of additional BitTorrent tracker’s announce URI. These URIs are not affected by --bt-exclude-tracker option because they are added after URIs in --bt-exclude-tracker option are removed.

Set the connect timeout in seconds to establish connection to tracker. After the connection is established, this option makes no effect and --bt-tracker-timeout option is used instead. Default: 60

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

Set timeout in seconds. Default: 60

Set host and port as an entry point to IPv4 DHT network.

Set host and port as an entry point to IPv6 DHT network.

Change the IPv4 DHT routing table file to PATH. Default: $HOME/.aria2/dht.dat

Change the IPv6 DHT routing table file to PATH. Default: $HOME/.aria2/dht6.dat

Specify address to bind socket for IPv6 DHT. It should be a global unicast IPv6 address of the host.

Set UDP listening port for both IPv4 and IPv6 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

Set timeout in seconds. Default: 10

Enable IPv4 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: true

Enable IPv6 DHT functionality. If a private flag is set in a torrent, aria2 doesn’t use DHT for that download even if true is given. Use --dht-listen-port option to specify port number to listen on. See also --dht-listen-addr6 option.

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

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

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.

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

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

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

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, random byte data are added to make its length 20 bytes. Default: aria2/$VERSION-, $VERSION is replaced by package version.

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

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

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

If true or mem is specified, when a file whose suffix is ".meta4" or ".metalink" or content type of "application/metalink4+xml" or "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

The file path to .meta4 and .metalink file. Reads input from stdin when - is specified. You are not required to use this option because you can specify .metalink files without -M.

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

The language of the file to download.

The location of the preferred server. A comma-delimited list of locations is acceptable, for example, jp,us.

The operating system of the file to download.

The version of the file to download.

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

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

Enable JSON-RPC/XML-RPC server. It is strongly recommended to set username and password using --rpc-user and --rpc-passwd option. See also --rpc-listen-port option. Default: false

Listen incoming JSON-RPC/XML-RPC requests on all network interfaces. If false is given, listen only on local loopback interface. Default: false

Specify a port number for JSON-RPC/XML-RPC server to listen to. Possible Values: 1024-65535 Default: 6800

Set max size of JSON-RPC/XML-RPC request. If aria2 detects the request is more than SIZE bytes, it drops connection. Default: 2M

Set JSON-RPC/XML-RPC password.

Set JSON-RPC/XML-RPC user.

Restart download from scratch if the corresponding control file doesn’t exist. See also --auto-file-renaming option. Default: 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

Always resume download. If true is given, aria2 always tries to resume download and if resume is not possible, aborts download. If false is given, when all given URIs do not support resume or aria2 encounters N URIs which does not support resume (N is the value specified using --max-resume-failure-tries option), aria2 downloads file from scratch. See --max-resume-failure-tries option. Default: true

Enable asynchronous DNS. Default: true

Comma separated list of DNS server address used in asynchronous DNS resolver. Usually asynchronous DNS resolver reads DNS server addresses from /etc/resolv.conf. When this option is used, it uses DNS servers specified in this option instead of ones in /etc/resolv.conf. You can specify both IPv4 and IPv6 address. This option is useful when the system does not have /etc/resolv.conf and user does not have the permission to create it.

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

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

Download file only when the local file is older than remote file. This function only works with HTTP(S) downloads only. It does not work if file size is specified in Metalink. It also ignores Content-Disposition header. If a control file exists, this option will be ignored. This function uses If-Modified-Since header to get only newer file conditionally. When getting modification time of local file, it uses user supplied filename(see --out option) or filename part in URI if --out is not specified. To overwrite existing file, --allow-overwrite is required. Default: false

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

Run as daemon. The current working directory will be changed to / and standard input, standard output and standard error will be redirected to /dev/null. Default: false

Disable IPv6. This is useful if you have to use broken DNS and want to avoid terribly slow AAAA record lookup. Default: false

Enable IPv6 name resolution in asynchronous DNS resolver. This option will be ignored when --async-dns=false. Default: false

Enable directI/O, which lowers cpu usage while allocating/checking files. Turn off if you encounter any error. Default: true

Specify the method for polling events. The possible values are epoll, kqueue, port, poll and select. For each epoll, kqueue, port and poll, it is available if system supports it. epoll is available on recent Linux. kqueue is available on various *BSD systems including Mac OS X. port is available on Open Solaris. The default value may vary depending on the system you use.

Specify file allocation method. 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. Possible Values: none, prealloc, falloc Default: prealloc

Print sizes and speed in human readable format (e.g., 1.2Ki, 3.4Mi) in the console readout. Default: true

Bind sockets to given interface. You can specify interface name, IP address and hostname. Possible Values: interface, IP address, hostname

Set maximum number of download result kept in memory. The download results are completed/error/removed downloads. The download results are stored in FIFO queue and it can store at most NUM download results. When queue is full and new download result is created, oldest download result is removed from the front of the queue and new one is pushed to the back. Setting big number in this option may result high memory consumption after thousands of downloads. Specifying 0 means no download result is kept. Default: 1000

When used with --always-resume=false, aria2 downloads file from scratch when aria2 detects N number of URIs that does not support resume. If N is 0, aria2 downloads file from scratch when all given URIs do not support resume. See --always-resume option. Default: 0

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

For BitTorrent, a command specified in --on-download-complete is called after download completed and seeding is over. On the other hand, this option set the command to be executed after download completed but before seeding. See Event Hook for more details about COMMAND. Possible Values: /path/to/command

Set the command to be executed after download completed. See See Event Hook for more details about COMMAND. See also --on-download-stop option. Possible Values: /path/to/command

Set the command to be executed after download aborted due to error. See Event Hook for more details about COMMAND. See also --on-download-stop option. Possible Values: /path/to/command

Set the command to be executed after download was paused. See Event Hook for more details about COMMAND. Possible Values: /path/to/command

Set the command to be executed after download got started. See Event Hook for more details about COMMAND. Possible Values: /path/to/command

Set the command to be executed after download stopped. You can override the command to be executed for particular download result using --on-download-complete and --on-download-error. If they are specified, command specified in this option is not executed. See Event Hook for more details about COMMAND. Possible Values: /path/to/command

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

Fetch URIs in the command-line sequentially and download each URI in a separate session, like the usual command-line download utilities. Default: false

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

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

Disable loading aria2.conf file.

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

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

Make aria2 quiet (no console output). Default: false

Validate chunk of data by calculating checksum while downloading a file if chunk checksums are provided. Default: true

Remove control file before download. Using with --allow-overwrite=true, download always starts from scratch. This will be useful for users behind proxy server which disables resume.

Save error/unfinished downloads to FILE on exit. You can pass this output file to aria2c with -i option on restart. Please note that downloads added by aria2.addTorrent and aria2.addMetalink RPC method and whose metadata could not be saved as a file are not saved.

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

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

Hostname of the server. Required.

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

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

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.

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.

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

Last contact time in GMT with this server, specified in the seconds since the Epoch(00:00:00 on January 1, 1970, UTC). Required.

ERROR is set when server cannot be reached or out-of-service or timeout occurred. Otherwise, OK is set.

GID(or gid) is the key to manage each download. Each download has an unique GID. Currently GID looks like an integer, but don’t treat it as integer because it may be changed to another type in the future release. Please note that GID is session local and not persisted when aria2 exits.