Not seeing syslogs when syslog server is added by its host name -

i have kiwi syslog server running on pc,when add ip address of sys log server device i'm able see syslogs on server side. if add host name of syslog server syslog-ng.conf file of device,i not see logs on server side.

i added below command syslog-ng.conf file

destination df_remote_1 {udp("target_host");};

log { source(s_all); filter(f_remote); destination(df_remote_1);};

i have added entries "/etc/reolv.conf" file holds dns config.

i'm able ping host name device,but not see logs? please guide me on this?

check if messages reach target host using tcpdump/wireshark. maybe there firewall rule somewhere blocks packages.