For a particular sourcetype I am facing log ingestion issue. Getting below error.
As checked with the team, this log file can not be split. So is there any solution to resolve this issue.
That's a warning, not an error. The file will be ingested, but while Splunk is busy with it other monitored files are ignored.
Consider standing up a separate UF on that server just for the large files.
Also, make sure maxKBps in limits.conf is set to 0 or the largest value the network can support.