Originally Posted by rknichols
You will have to find out why the filesystem has become read-only. Perhaps there is something in /var/log/messages that indicates what error caused that.
I don't have a clue, the disk was remounted and I was able to extract the files. What I observed until almost 48 hours of efforts are
if I move the tar.gz files using "cp", the md5sum are different
if I move the same files using "scp", the md5sum are same and I can extract the files without any problems using tar
It looks kinda strange, however, finally I was able to extract the files to a second server, even though the process took around 834 minutes to extract a 111gb tar file.
thanks to everyone who contributed to the question.