couldn't able to start rabbitmq server error description undef

Problem: Could not able to start rabbitmq server 3.5.5 in ubuntu 1404. Shows error description as undef

 BOOT FAILED  
 ===========  
 Error description:  
   undef  
 Log files (may contain more information):  
   ./../var/log/rabbitmq/rabbit@user.log  
   ./../var/log/rabbitmq/rabbit@user-sasl.log  
 Stack trace:  
   [{mnesia,system_info,[directory],[]},  
   {rabbit_mnesia,ensure_mnesia_dir,0,[]},  
   {rabbit_node_monitor,prepare_cluster_status_files,0,[]},  
   {rabbit,'-boot/0-fun-0-',0,[]},  
   {rabbit,start_it,1,[]},  
   {init,start_it,1,[]},  
   {init,start_em,1,[]}]  
 {"init terminating in do_boot",undef}  
 Crash dump was written to: erl_crash.dump  
 init terminating in do_boot (undef)  

./rabbitmq-server: 42: ./rabbitmq-server: cannot create ./../var/lib/rabbitmq/mnesia/rabbit@host-name.pid: Permission denied


This article explains how to install and start rabbitmq server from tar.gz or zip file

Latest rabbitmq binaries will be available in https://www.rabbitmq.com/download.html

 ./rabbitmqctl status  
 Status of node 'rabbit@user' ...  
 Error: unable to connect to node 'rabbit@user': nodedown  
 DIAGNOSTICS  
 ===========  
 attempted to contact: ['rabbit@user']  
 rabbit@user:  
  * connected to epmd (port 4369) on user  
  * epmd reports: node 'rabbit' not running at all  
          no other nodes on user  
  * suggestion: start the node  
 current node details:  
 - node name: 'rabbitmq-cli-4379@user'  
 - home dir: /root  
 - cookie hash: DF1wwqN1m3Yr/KRh3g47gA==  
 root@user:/home/krishna/rabbitmq_server-3.5.5/sbin#