1. Start two nodes on the same host. Perform some RPC calls between the two nodes.
The manual pages for rpc can be viewed here: http://erlang.org/doc/man/rpc.html
In one shell session:
$ erl -sname watson
% After both shells are running
1> rpc:call('holmes@my-laptop', erlang, nodes, []).
In another shell session:
$ erl -sname holmes
1> rpc:call('watson@my-laptop', erlang, get_cookie, []).
% After watson node is stopped
2> rpc:call('watson@my-laptop', erlang, nodes, []).
{badrpc,nodedown}
2. Repeat the first exercise with two nodes on a LAN.
Same as above, but with a common cookie specified on both computers, and node names in the rpc calls containing the full hostname to the server or IP address.
3. Repeat the first exercise with two nodes on separate networks.
Make sure port 4369 is open on both computers, and then choose a range of ports to open for communication between individuals nodes. Then run the same command as for exercise #2, but specify the range of open ports with the kernel inet_dist_listen_min <min port in the range> inet_dist_listen_max <max port in the range>.
4. Write a simple file server using the libraries in lib_chan.
Solution is in the exercise_4/ directory. My implementation is a very minimal file server. Compile the lib_chan and yaf server code:
cd exercise_4/
erlc *.erl
erlc lib_chan/*.erl
Then start the server in an erl shell:
erl -pa lib_chan -pa .
1> yaf_server:start().
lib_chan starting:"lib_chan.conf"
ConfigData=[{port,1234},
{service,yaf_server,password,"123files",mfa,yaf_server,
start_file_server_loop,
[{location,"shared_files"}]}]
In another shell make the client calls:
erl -pa lib_chan -pa .
1> {ok, Pid} = lib_chan:connect("localhost", 1234, "123files", yaf_server, []).
% List files
2> lib_chan:rpc(Pid, {ls, "/"}).
{ok,["afile.txt"]}
% Read a file
3> lib_chan:rpc(Pid, {read, "/afile.txt"}).
{ok,<<"You read a file from the server!\n">>}
% Write a new file
4>lib_chan:rpc(Pid, {write, "another_file.txt", "New file!!!"}).
ok