Fix: Unable to start TLS: SSL connect attempt failed error:14090086:SSL routines:ssl3_get_server_certificate:certificate verify failed when connecting to ldap master.Cannot determine services – exiting Rumi, September 1, 2018 My ZImbra 8.6 was throwing the following error once after my letsencrypt SSL got expired: Unable to start TLS: SSL connect attempt failed error:14090086:SSL routines:ssl3_get_server_certificate:certificate verify failed when connecting to ldap master.Cannot determine services – exiting The Fix: In order to fix the problem you need to modify the following… Continue Reading
Zimbra Letsencrypt SSL Renew – Zimbra 8.6 Rumi, September 1, 2018 Let’s Begin: This works if you already have an expired letsencrypt ssl certificate and assuming you have already deployed SSL in you zimbra system. However, if you come up here already, and would like to know how to setup letsencrypt on your system you may read my other article here:… Continue Reading
Zimbra – deleting all email in queue by sender Rumi, August 17, 2018January 15, 2022 As root user execute: /opt/zimbra/postfix/sbin/postqueue -p | tail -n +2 | awk ‘BEGIN { RS = “” } / sender@mail\.com/ { print $1 }’ | tr -d ‘*’ | /opt/zimbra/postfix/sbin/postsuper -d – To Delete ALL Messages From Queue /opt/zimbra/postfix/sbin/postsuper -d ALL or /opt/zimbra/common/sbin/postsupe -d ALL Another way to do this:… Continue Reading
Syslog server with Rsyslog and LogAnalyzer in Ubuntu 12 Rumi, August 17, 2018 Installing Rsyslog from repository First make sure you have the latest update of Ubuntu 12.04 LTS sudo apt-get update && sudo apt-get upgrade Adding PPA repository sudo add-apt-repository ppa:adiscon/v8-devel If you get this error: “add-apt-repository: command not found” Try installing this python-software-properties package apt-get install python-software-properties Update your apt cache… Continue Reading
Varnish daemon not listening on configured port – Hack for Debian or Ubuntu Rumi, August 9, 2018 If you’re already troubled with varnish on changing listening ports from default. Here’s a little hack that worked on my Debian and Ubuntu distribution. sudo apt remove varnish sudo apt-get purge varnish # I manually remove the 3 files in created in /etc/systemd/system/* sudo apt install varnish sudo nano /lib/systemd/system/varnish.service… Continue Reading
Install XRDP in Debian 9 Rumi, August 8, 2018 Install XRDP and TigerVNC server $ sudo apt install -y xrdp tigervnc-standalone-server Connect XRDP from Windows 10 Windows start button -> Windows Accesssories -> Remote Desktop Connection Input FQDN or IP address of XRDP server and connect to XRDP. XRDP RDP terminal will appear. Select “XVNC” Session and connect. Continue Reading
Create a Linux Router with DHCP services Rumi, August 5, 2018August 5, 2018 It’s pretty easy to build a Linux router even on a virutal machine. I’ve used virtualbox to create a LAN NAT router with DHCP services using webmin. However, I’m not going to cover on how to use a virtualbox VM 🙂 Let’s create the NAT Router first. On Webmin go… Continue Reading
Install wkhtmltopdf on Debian 8, 9 Rumi, August 3, 2018January 18, 2019 Installation on Debian 8 apt-get update aptitude install xfonts-base xfonts-75dpi fontconfig xvfb mkdir ~/src/wkhtmltopdf -p cd ~/src/wkhtmltopdf wget https://bitbucket.org/wkhtmltopdf/wkhtmltopdf/downloads/wkhtmltox-0.13.0-alpha-7b36694_linux-jessie-amd64.deb dpkg -i wkhtmltox-0.13.0-alpha-7b36694_linux-jessie-amd64.deb echo ‘xvfb-run –server-args=”-screen 0, 1024x768x24″ /usr/local/bin/wkhtmltopdf $*’ > /usr/bin/wkhtmltopdf.sh chmod a+rx /usr/bin/wkhtmltopdf.sh ln -s /usr/bin/wkhtmltopdf.sh /usr/local/sbin/wkhtmltopdf /usr/local/sbin/wkhtmltopdf https://www.google.fr output.pdf Installation on Debian 9 Continue Reading
Find Ethernet Connection Speed Rumi, July 29, 2018 Type the following command to get speed for eth0: $ ethtool eth0 | less OR $ ethtool eth0 | grep -i speed You can also use the following two commands: $ dmesg | grep eth0 | grep up $ dmesg | grep bond0 | grep up OR use the command… Continue Reading
DNS Forwarder and Transfer using Bind and Webmin Rumi, June 29, 2018 To point your BIND based DNS server to use OpenDNS resolvers for external resolution you need to modify the named.conf.options and add the OpenDNS resolvers as forwarders. This can be done in two ways: via the command line, Shell\SSH via a GUI if you have Webmin installed on your BIND server Shell\SSH… Continue Reading