EFS - NFS Client Error while creating a directory or file: Remote I/O Error

Hi All,

I setup a DataSync environment and create a task to transfer data from EFS to EFS.

I created 2 different EFS. Source EFS in us-west-1 and target EDS in us-east-1. I created 2 locations. When I started the task it gives an error. Then I tried to regenerate the same error which is coming from source site and there was a hint in the datasync document that says run the following command

sudo mount -t nfs -o nfsvers=4.1 ip-10-1-1-57.us-west-1.compute.internal:/ /efs

I run the command and mounted my NFS Server. When I tried to create a directory or file it gives the below error:
[root@ip-10-1-1-191 efs]# sudo mkdir test1
mkdir: cannot create directory ‘test1’: Input/output error

[root@ip-10-1-1-191 efs]# ls -al
ls: cannot access test2: Remote I/O error
ls: cannot access test1: Remote I/O error
total 4
drwxrwxrwx 4 root root 6144 Aug 16 21:22 .
drwxrwxrwx 19 root root 268 Aug 16 19:31 ..
?????????? ? ? ? ? ? test1
?????????? ? ? ? ? ? test2

EFS - NFS Server and NFS Client are in the same region and availability zone. I do not have any problem with mounting the EFS and NFS Server.

NFS SERVER COMMANDS USED on EC2 (10.1.1.57)
sudo su
cd /
sudo yum update -y
sudo yum -y install nfs-utils
sudo mkdir /efs

sudo nano etc/exports
sudo cat etc/exports
OUTPUT:
/efs *(rw,sync,fsid=0)

sudo service nfs start
sudo mount -t nfs4 -o nfsvers=4.1,rsize=1048576,wsize=1048576,hard,timeo=600,retrans=2,noresvport fs-a25576bb.efs.us-west-1.amazonaws.com:/ efs

sudo exportfs -r
sudo showmount -e
OUTPUT:
Export list for ip-10-1-1-57.us-west-1.compute.internal:
/efs *

df -k
OUTPUT:
fs-a25576bb.efs.us-west-1.amazonaws.com:/ 9007199254739968 0 9007199254739968 0% /efs

NFS CLIENT COMMANDS USED on EC2 (10.1.1.191)
sudo su
cd /
sudo yum update -y
sudo yum -y install nfs-utils
sudo mkdir /efs
sudo service nfs start
sudo mount -t nfs -o nfsvers=4.1 ip-10-1-1-57.us-west-1.compute.internal:/ /efs
df -k
OUTPUT
ip-10-1-1-57.us-west-1.compute.internal:/ 9007199254739968 0 9007199254739968 0% /efs

[root@ip-10-1-1-191 efs]# sudo mkdir test
mkdir: cannot create directory ‘test’: Remote I/O error

[root@ip-10-1-1-191 efs]# ls -al
ls: cannot access test: Remote I/O error
total 4
drwxrwxrwx 3 root root 6144 Aug 16 22:58 .
drwxrwxrwx 19 root root 268 Aug 16 22:55 ..
?????????? ? ? ? ? ? test

Need an urgent help
Best Regards,
Hakan Korkmaz