Category Archives: Servers

Linux : Package package-name.rpm is not signed

Having the following error trying to install a unsigned package from Yum repository on CentOS/RHEL? Unless you get an officially signed package(s), you will need to override/accept the installation of unsigned package (if you trust the source/issuer, of course). If installing a locally located rpm file(s), you may use the command “rpm -ivh package-name.rpm“. If… Read More »

Windows : RDP An authentication error has occurred. The function requested is not supported

Since the latest Windows Updates, you might be encountering the following error when you RDP to another computer or server : An authentication error has occurred. The function requested is not supported Remote computer: This could be due to CredSSP encryption oracle remediation. For more information, see This is basically due to the fact… Read More »

Dell : How to install a custom issued SSL certificate on iDRAC

If you already have a certificate generated by a certificate authority (or maybe a wildcard certificate), you can use the following procedure to configure it on your iDRAC, so you can get rid of the browser security warning. We will use the iDRAC “racadm” command line utility (if you do not have it already, you… Read More »

MacOS : Unable to negotiate with port 22: no matching cipher found

Having the following issue connecting to a device using SSH after upgrading to macOS High Sierra 10.13.2? Unable to negotiate with port 22: no matching cipher found. Their offer: aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,arcfour,aes192-cbc,aes256-cbc, This is an expected behavior if you attempt to connect to a legacy system or network device running older version of SSH. To workaround… Read More »

Linux : How to show connected client of NFS export on the server?

Here is how to quickly show the connected clients to a NFS server. It might be useful to know before rebooting the server! On the server, execute the following command (replace <> with the NFS server IP address) :

Example :

You should see a similar output : tcp 0 0… Read More »

Linux : How to add rc.local in Debian 9

On Debian 9, the traditional “rc.local” has been deprecated. For traditional Linux users and administrators, there is a way to get it back using SystemD. See the procedure below : 1. Edit the non-existing file “rc-local.service” :

1.1. Add the following content to “/etc/systemd/system/rc-local.service” :

2. Edit the “rc.local” file :

 … Read More »

Linux : R1Soft failed backup of LVM configuration

Having the following error while executing a R1Soft backup on a Linux server? Failed backup of LVM configuration Failed to execute command ‘lvm.static pvs -o pv_fmt,pv_uuid,dev_size,pv_name,pv_mda_free,pv_mda_size,pv_all,seg_all,pvseg_all,vg_all,lv_all –nameprefixes –noheadings –units b –nosuffix –unquoted’ This seem to be related to the latest version. Apparently Idera are aware of the issue and working on a permanent fix. In… Read More »