:econnrefused when starting named erl/iex

I am not entirely sure what is going on here, but I am on an AWS ubuntu box trying to debug an elixir deployment issue and am unable to start a simple session when specifying a node name or sname:

If I start a console with either erl -sname a or iex --sname, I get the following error: Protocol ‘inet_tcp’: register/listen error: econnrefused.

Everything I’ve read points to epmd, but epmd is running. netstat -ntlp:

Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address           Foreign Address         State       PID/Program name
tcp        0      0 0.0.0.0:4369            0.0.0.0:*               LISTEN      8931/epmd       
tcp        0      0 0.0.0.0:22              0.0.0.0:*               LISTEN      1017/sshd       
tcp6       0      0 :::4369                 :::*                    LISTEN      8931/epmd       
tcp6       0      0 :::22                   :::*                    LISTEN      1017/sshd 

The full backtrace from erl -sname a -init_debug is:

{progress,preloaded}
{progress,kernel_load_completed}
{progress,modules_loaded}
{start,heart}
{start,error_logger}
{start,application_controller}
{progress,init_kernel_started}
{apply,{application,load,[{application,stdlib,[{description,"ERTS  CXC 138 10"},{vsn,"3.3"},{id,[]},{modules,[array,base64,beam_lib,binary,c,calendar,dets,dets_server,dets_sup,dets_utils,dets_v8,dets_v9,dict,digraph,digraph_utils,edlin,edlin_expand,epp,eval_bits,erl_anno,erl_bits,erl_compile,erl_eval,erl_expand_records,erl_internal,erl_lint,erl_parse,erl_posix_msg,erl_pp,erl_scan,erl_tar,error_logger_file_h,error_logger_tty_h,escript,ets,file_sorter,filelib,filename,gb_trees,gb_sets,gen,gen_event,gen_fsm,gen_server,gen_statem,io,io_lib,io_lib_format,io_lib_fread,io_lib_pretty,lib,lists,log_mf_h,maps,math,ms_transform,orddict,ordsets,otp_internal,pool,proc_lib,proplists,qlc,qlc_pt,queue,rand,random,re,sets,shell,shell_default,slave,sofs,string,supervisor,supervisor_bridge,sys,timer,unicode,win32reg,zip]},{registered,[timer_server,rsh_starter,take_over_monitor,pool_master,dets]},{applications,[kernel]},{included_applications,[]},{env,[]},{maxT,infinity},{maxP,infinity}]}]}}
{progress,applications_loaded}
{apply,{application,start_boot,[kernel,permanent]}}
Protocol 'inet_tcp': register/listen error: econnrefused

Any suggestions on how to get this fixed would be greatly appreciated…