Category Archives: Servers

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 0.0.0.0 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 0.0.0.0 port 22: no matching cipher found. Their offer: aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,arcfour,aes192-cbc,aes256-cbc,rijndael-cbc@lysator.liu.se 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 0 192.168.45.32:2049 192.168.45.52:840… 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 »

Windows : Convert Server 2016 Standard to Datacenter

Windows evolved a lot in the last years, what was once a headache for system administrators is now behind us since a few years. Microsoft now allow to convert a installed Windows Server 2016 Standard to Datacenter without having to re-install. To achieve this, you will need to have in hand your Windows Server 2016… Read More »

Windows : BSOD 0x0000007E (0xFFFFFFFFC0000005, 0xFFFFF880018C9836, 0xFFFFF880009A9008, 0xFFFFF880009A8860)

I had the luck of experiencing the following blue screen on a Windows Server 2008 R2 domain controller server at boot lately : *** STOP: 0x0000007E (0xFFFFFFFFC0000005, 0xFFFFF880018C9836, 0xFFFFF880009A9008, 0xFFFFF880009A8860) Related facts with this server : – Haven’t been rebooted since two years – Windows Updates haven’t been run for two years – Running minimalistic… Read More »

Linux : Apache Invalid command ‘ProxyPreserveHost’

Having the following error output trying to start, restart or do a configtest on Apache server? Invalid command ‘ProxyPreserveHost’, perhaps misspelled or defined by a module not included in the server configuration This is likely caused because mod_proxy module is not present or disabled. To enable it, look out for the following in the main… Read More »