Missing users after micctrl --resetconfig

[Ole_Saastad]

After issuing the micctrl --resetconfig command a lot of users are created on the phi system:

wc -l /opt/intel/mic/filesystem/mic0/etc/passwd show 363 entires e.g. users, however the /etc/passwd file contain much more,

wc -l /etc/passwd yield 966. The home directories also show the same, 363 directories are created while there are far more on the host.

For those 363 entires all seems to work fine, passwordless login etc. There are some users with warning about ssh keys, but these are not the ones that are missing. 

What can cause the micctrl to only include parts of the /etc/passwd file and skip a large range of users ?

Ole

[Frances_R_Intel · Accepted solution]

Did you check to see what the UID range is? In the /etc/mpss/mic0.conf file, there should be a line similar to:

UserAuthentication Local 500 65000

In this example, all users with a UID in the range 500 to 65000 on the host should end up in the passwd file for the coprocessor. If the range in your mic0.conf file does not include all the UIDs you want, you can change that value by either editing mic0.conf and rerunning "micctrl -- resetconfig" or by running "micctrl --configuser=local --low=<low end of range> --high=<high end of range>". Just be sure the range you use doesn't include any special users like root that will get created automatically and you need to leave room for micuser (which I believe is 400 by default.)

If all your users already fall within the UserAuthentication range then something else is going on that we need to look into.

[Ole_Saastad]

Thanks, easy to fix if you know the answer.

Not easy to figure out unless you skim through the config files routinely.

Regards,

Ole

[Russell_D_]

I am having the same problem (only users through uid 65535 are getting added) under MPSS 3.2.1 for Linux, but when I try setting the UserAuthentication parameter to something like "UserAuthentication Local 1000 100000" and running micctrl --resetconfig, I get:

"mic0: UserAuthentication parameter deprecated and non functional - Removing"

I thought I would try setting UserAuthentication to "none" and managing the passwd files on the MICs manually, but doing that gets the same error about the UserAuthentication parameter being deprecated.

Can anybody clue me in to what the new method of controlling user accounts is? I looked through the Cluster Setup Guide and the Advanced Configuration Guide, but both documents appear to be out of date and still referencing the UserAuthentication parameter.

[Frances_R_Intel]

Unfortunately, in current MPSS (mpss-3.2.1), the UserAuthentication parameter has been removed from the micX.conf file. The way to set the parameter now is with micctrl. In the MPSS User Guide, section 15.2.1 describes how to do this on the "micctrl --initdefaults" command; section 15.3.3 shows how to do this on the "micctrl --userupdate" command. Neither of these has any way to change the range of uids.

This command should cause all users in the host's password file to appear in the coprocessor mic0's password file and the passwords to be copied to the shadow file:

[bash]

micctrl --userupdate=overlay --pass=shadow mic0

[/bash]

I will keep looking around to see if there is something I missed. But if the userupdate option still cuts off the users at 65535, let me know and I will report it to the MPSS developers.

[Russell_D_]

Thanks for the new syntax. The --userupdate=overlay (and --userupdate=merge) option does in fact not add any users with uid > 65535 on our system (RHEL 6.5 with mpss-3.2.1). The users can be added one at a time with micctrl --useradd, although that isn't the most convenient method.

Thanks,

Rusty

[Frances_R_Intel]

OK, this uid limit sounds like something it would be good to ask the developers to change. I will do that. In the meantime, at least you are able to work around the issue, although somewhat painfully.

[Srikanth_K_]

[root@ihpc ~]# micctrl --userupdate=overlay --pass=shadow mic0
[Warning] mic0: Create home directory /var/mpss/mic0/root failed: File exists
[Warning] mic0: Create home directory /var/mpss/mic0/home/micuser failed: File exists

Please help me .... ssh -ing mic0 asks for a password, i tried keying-in the user root password and doesn't authenticate. It keeps on asking for the password .. please help me on this.

The same happens with other users also . . 

[Frances_R_Intel]

The warning messages are ok - those are just saying that, at some point in the past, the home directories for root and micuser on the coprocessor were created. 

As to what is causing ssh to demand a password, there are two likely causes: 1) The '.ssh' directory was not created in the user's home directory on the coprocessor or wasn't populated with the correct files or 2) When the ssh keys were generated, a passphrase was entered.

The first thing to check would be that the '.ssh' directory exists in the user's home directory on the coprocessor. If you are not NFS mounting the user's home directory on the coprocessor, go to /var/mpss/mic0/home on the host and make sure each user home directory in there has a '.ssh' directory and that directory contains the same keys as the '.ssh' directory in the user's host home directory. Reboot the coprocessor and try again. You can also use micctrl to copy the '.ssh' directories, one user at a time or use scp to copy the files from the host to the coprocessor if you don't want to reboot the coprocessor.

If that isn't the problem, try regenerating the ssh keys and do not specify a passphrase. Copy the keys to the '.ssh' directory in the user's home directory for the coprocessor, as in the previous paragraph and try ssh-ing into the coprocessor again.

If you are using LDAP or NIS then things will be a little different - look in the MPSS user's guide for information.

Let me know if this doesn't solve your problem.