The services can also be started separatedly with ./shard.py, ./cdc.py, ./block_service.py, and ./shuckle.py. They are all needed to operate a filesystem, and the shard must be 256.

With shuckle running, you can navigate to http://localhost:5000 to see a view of all block services.

Mounting EggsFS using FUSE

% ./python/eggsfuse.py <mount-point>

Now you can use EggsFS normally. You can use --debug and --debug-fuse for debugging output.

Note that EggsFS' files are immutable! You'll get EROFS ("read only filesystem") if you try to modify files. In general, you'll have success writing files by opening them, writing to them in an append-only manner, and then closing them.

Sometimes you might get errors which are a bit more surprising than EROFS:

% echo blah > foobar
echo: write error: no such file or directory

The reason for this is that foobar is created by the shell and then opened again before being closed. This means that foobar does not exist yet, and you get the above. After this failure foobar will be close and will materialized, as empty.

Using the command line client

% ./python/basic_client.py ls /
% ./python/basic_client.py copy_into /cdc.py cdc.py # copies the contents of cdc.py into the EggsFS file /cdc.py
% ./python/basic_client.py cat /cdc.py # prints out the contents of cdc.py
% ./python/basic_client.py mkdir /blah
% ./python/basic_client.py echo_into /blah/baz 'hello' # creates file /blah/baz with string 'hello' in it

Testing

./python/tests.py

We try to test all operations and all error conditions. The CDC test driver can inject shard failures to test cases where shard requests go wrong.

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