Author Archives: Kaven G.

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About Kaven G.

System Engineer / Network Administrator

Linux : perl: warning: Setting locale failed

You probably noticed the following output on your console after logging to your newly installed CloudLinux server :

perl: warning: Setting locale failed.
perl: warning: Please check that your locale settings:
LANGUAGE = (unset),
LC_ALL = (unset),
LC_CTYPE = “UTF-8”,
LANG = “en_US.UTF-8”
are supported and installed on your system.
perl: warning: Falling back to the standard locale (“C”).
perl: warning: Setting locale failed.
perl: warning: Please check that your locale settings:
LANGUAGE = (unset),
LC_ALL = (unset),
LC_CTYPE = “UTF-8”,
LANG = “en_US.UTF-8”
are supported and installed on your system.
perl: warning: Falling back to the standard locale (“C”).

This does not represent any major issue, but can be quite annoying over time. To get rid of these notifications, do the following procedure.

1. Edit the following file using your favorite text editor :

2. Append the following :

NOTE : The file should be blank by default. You may adjust the above to meet your requirements if using different language or encoding.

Linux : CloudLinux installation error “You have third-party kernel module rpm installed”

Ending up with the following error trying to install CloudLinux?

You have third-party kernel module rpm installed.
It’s not compatible with CloudLinux kernel.
Please contact CloudLinux support at https://helpdesk.cloudlinux.com

In my case, this was because of the “kmod-vmware-tools-vmxnet3” module, since it was on a VMware guest machine.

Since removing it isn’t an option and I don’t see any good reason why this couldn’t work with CloudLinux, I decided to find a workaround to bypass the check for custom kernel modules.

Using the following installation parameter did the trick :

So let’s assume we are installing CloudLinux with a IP based license, the command would look like this :

Windows : The following error occurred attempting to join the domain “domain.tld”: The request is not supported.

Ending up with the following error trying to join a server or workstation to an existing Active Directory domain?

The following error occurred attempting to join the domain “domain.tld”:
The request is not supported.

Additionally, if you have a look at the EventViewer, you can see the following log entries under the following logging facility :

Windows Logs > System

The machine <ComputerNetBIOSname> attempted to join the domain <domain.tld> but failed. The error code was 50.
The machine<ComputerNetBIOSname> attempted to join the domain <domain.tld> but failed. The error code was 1332.

In my case, the machine was a secondary domain controller that did not deployed properly and hanged for ages on “dcpromo”. I had to force reboot the machine and of course it caused some troubles.

To resolve this matter, I did the following steps :

1. Disjoin the domain

2. Delete the computer account on the domain in “dsm.msc”

3. Open the registry editor and do the steps below.

WARNING! Do a full registry backup before doing anything. I also highly suggest that you do also backup the individual keys you are about to delete or modify.

3.1. Find the string values below and delete their content (which should match your domain name) :

3.2. Find the keys below and delete them entirely. Create new empty keys with the same name.

NOTE : In my case, these were the only one I had to remove. I used the “Find Next” function to search for my domain name in the registry, I would suggest you do the same in case you still have some left over.

4. Reboot the server.

4.1. OPTIONAL (In my case, remember I was having this issue deploying a SDC, if the same thing happened to you, then remove the Active Directory Domain role service and reboot again).

5. You may now join the computer back again on the domain.

NOTE : This procedure has been performed on Windows Server 2012 R2

JunOS : Warning aggregated-ether-options link-speed no kernel value

You probably have seen the following on your Juniper JunOS device :

dcd[15676]: ae60 : Warning: aggregated-ether-options link-speed no kernel value! default to 0
dcd[1103]: ae60 : aggregated-ether-options link-speed set to kernel value of 1000000000

This mean that your aggregated interface (ae) does not have any link-speed statement. By the book, this statement should be declared in your configuration such as :

So let’s say we have a bond composed of 2 x 10 Gbps and the interface name is ae60 :

You may now commit your configuration, the notification should disappear from the system logs.

Mac : How to uninstall LogMeIn

LogMeIn remote control software cannot be removed without traces by just removing the .app icon/folder from the Application directory like you used to do with the majority of software (it will leave the finder tray icon, will attempt to start on boot, etc.).

There is an easy way using the uninstaller script to achieve this task.

1. Open the terminal :

Go > Utilities > Terminal

2. Run the following command :

NOTE : You will be prompted for your administrator’s credentials, just enter your password and hit enter.

Category: Mac

VMware : Access to resource settings on the host is restricted to the server which is managing it

If you are running vSphere vCenter, you might have encountered the following error trying to modify virtual hardware (vDisk) on a VM directly from a host instead of doing it through vCenter :

Access to resource settings on the host is restricted to the server which is managing it

This behaviour is actually expected, some sort of lock is added to the VM configuration when hosts are joined to vCenter to avoid modification outside of vCenter. Of course, the proper way of doing it is performing this action through vCenter, however this might be necessary if the VM is the vCenter itself!

To temporarily workaround this issue, follow these easy steps :

1. Enable SSH on the host that currently hold this VM :

Configuration > Security Profile > Services > Properties > SSH > Options…

2. Login to the host using SSH.

3. Run the following command to stop the vCenter agent and restart the vCenter daemon :

NOTE : At this point, the vCenter reference has been removed from the host along with the lock.

4. Edit the ressource on your VM.

5. Start the vCenter Agent once you are done editing the VM :

6. Disable SSH on the host.

Configuration > Security Profile > Services > Properties > SSH > Options…

Linux : fuser command not found on CentOS/RHEL 7

You may have encountered the following issue trying to run “fuser” command on CentOS/RHEL 7 :

fuser: command not found

Many system administrators turn to do minimalist installation with version 7, unfortunately this even cut some critical basic components such as “traceroute, ifconfig, fuser, etc.” which in my opinion should be a part of a minimal install!

Anyway, you may have tried to install the command with Yum without success, because it is a part of a package named “psmisc.

Simply use the following command to install fuser :

Windows : Outlook IMAP server wants to alert you to the following: fatal error: no such file or directory

You may encounter the following error message with Microsoft Outlook, while browsing your IMAP tree folders, sending a message or moving message across them :

IMAP server wants to alert you to the following: fatal error: no such file or directory

I have observed this behaviour with a mailbox and a Linux mail servers (Qmail, Postfix, Exim) running “courier-imap”. The reason seem to be related to the folder index file (courierimapsubscribed), which does not have the full folder index any more.

To resolve this matter, do the following :

1. Make sure that the affected user that is experiencing the issue does not have any mail client opened anywhere
2. On the IMAP/mail server, browse to the user mailbox
3. Locate the folder index file named “courierimapsubscribed”
4. Move the courierimapsubscribed file as courierimapsubscribed.old
5. Open the mail client again, the index will be regenerated (it may take a little while on large mailbox).

VMware : Converter return general system error occurred: Network error. key can’t be retrieved.

Having the following error trying to convert a live CentOS/RHEL Linux system with VMware Converter?

FAILED: A general system error occurred:
Network error. Host x.x.x.x key can’t be retrieved. (return code 2)

In my case, this happened while converting a RHEL 5.11 server with VMware Converter 6.1.1.

If you went through the following :

– SSH configuration is allowing root to access the system remotely from port 22
– IPtables allow connection on port 22
– You are running Converter version 5.5.1 or greater (there is a known issue with older version that aren’t supporting DSA keys)

Then it might be caused by the “hosts.allow” parameter. Edit the following file :

And make sure you have the following entered (usually this file is blank on vanilla systems) :

Alternatively, you can restrict the subnet from where the connection come from by entering the following (this example will allow subnet “10.10.5.0/24) :

Restart the network service :

JunOS : Alarm Management Ethernet Link Down

Having the red alarm led on but nothing is wrong with your JunOS powered Juniper device?

First, look out what alarm is triggered by issuing the following command :

If absolutely nothing is really wrong, you will see the following alarm :

Alarm time Class Description
2016-01-20 07:11:59 UTC Major Management Ethernet Link Down

The alarm above is triggered if the out-of-band management port on the back (for EX series switch for example) or the MGMT ethernet port on the MX serie routers isn’t connected. If you know what you are doing and use in-band management, you can “safely” disregard this error and tell your device to ignore it using the following command :

NOTE : Best practice speaking, I would recommended to use an out-of-band network in addition to the in-band management. Additionally, if you really want to have the peace of mind, I would also connect the device to a serial server appliance! (especially if you are managing transit provider devices) it might save you one day!