ejabberd : Other users are not visible after login

Uncomment line

{mod_shared_roster,[]},

in config file of ejabberd and restart ejabberd.

config file - /etc/ejabberd/ejabberd.cfg 

Now you can see option "shared roster group".

Create a group and add users in the group. You can see all users of same group after login.

ejabberd : No other options except virtualhosts in admin

ejabberd : All links missing, partial admin appears

sudo nano /etc/ejabberd/ejabberd.cfg


Find lines
{acl, admin, {user, "", "localhost"}}.
%% Hostname
{hosts, ["localhost"]}.

and replace it with

{acl, admin, {user, "admin", "localhost"}}.
%% Hostname
{hosts, ["localhost"]}.



Restart ejabberd

ERROR: S3 error: 400 (InvalidRequest): The authorization mechanism you have provided is not supported. Please use AWS4-HMAC-SHA256.

Solution :
Your s3cmd has older version, you need to upgrade it. Download latest one and use the file everywhere.
https://sourceforge.net/projects/s3tools/files/s3cmd/1.6.1/
I faced this problem on 1.1 version of s3cmd, I downloaded latest and got 1.6. After that I did not get the error.

How to use the downloaded folder.
1) Extract the folder and open it.
2) Now run your s3cmd command using this downloaded folder.

 /home/ubuntu/s3cmd-1.6.1/s3cmd ls s3://

/home/ubuntu/s3cmd-1.6.1/s3cmd -c /home/ubuntu/.s3cfg put /tmp/file.sql s3://bucketname