How to split and join large files

Sometimes it might be necessary to chop up a large file into several parts (e.g. to place it on drives that are to small for the whole file). Keep in mind that corruption to any of the parts will result in a corrupt file once it is stiched back together.

To split a large file:

split -b 1m /path/to/large/file /path/to/output/file/prefix

-b defines the size of the chunks (1m stands for 1 megabyte). Please refer to man split for all the options the tool offers.

This will give you a bunch of files whose names start with the defined prefix and a incremental suffix (starting with aa depending how many parts need to be created).

To join the parts back into one file:

cat prefix* > new_filename