Failed to start Elasticsearch | 'failed' state with result 'signal'

No need for seed_hosts if is the single node. Usually this configuration in elasticsearch.yml is enough for the single node.

cluster.name: es
node.name: node1
path.data: /var/lib/elasticsearch
path.logs: /var/log/elasticsearch

network.host: 0.0.0.0
http.port: 9200
discovery.type: single-node