[Redis] 레일즈, 레디스 서버가 갑자기 안될 때 오류 해결

redis 서버 시작이 안되는 경우

오류메세지

5556:C 26 Apr 2021 14:30:30.637 # oO0OoO0OoO0Oo Redis is starting oO0OoO0OoO0Oo
5556:C 26 Apr 2021 14:30:30.637 # Redis version=6.2.1, bits=64, commit=ba815b3a, modified=1, pid=5556, just started
5556:C 26 Apr 2021 14:30:30.637 # Warning: no config file specified, using the default config. In order to specify a config file use redis-server /path/to/redis.conf
5556:M 26 Apr 2021 14:30:30.638 # You requested maxclients of 10000 requiring at least 10032 max file descriptors.
5556:M 26 Apr 2021 14:30:30.638 # Server can't set maximum open files to 10032 because of OS error: Operation not permitted.
5556:M 26 Apr 2021 14:30:30.638 # Current maximum open files is 4096. maxclients has been reduced to 4064 to compensate for low ulimit. If you need higher maxclients increase 'ulimit -n'.
5556:M 26 Apr 2021 14:30:30.638 * monotonic clock: POSIX clock_gettime
5556:M 26 Apr 2021 14:30:30.638 # Could not create server TCP listening socket *:6379: bind: Address already in use

redis-cli ping
핑퐁이 되나 확인했더니 잘 된다

ps -ef |grep redis
사용 중인 포트를 확인하고 kill -9로 해당 서버를 꺼주고 다시 시작한다

Rails에서 서버 시작이 안되는 경우

A server is already running 메세지를 받을 시
kill -9 $(lsof -i tcp:3000 -t)