Manage Dell C1100 CS24-TY Servers Using IPMI Tool

Dell C1100 servers can be managed using the IPMI tool which interfaces with the low level BMC interface.  Dell has also released a bmc specific utility that compliments the generic ipmitool to better configure and manage specific settings that are difficult to configure using ipmitool on its own.

Here's how to use both ipmitool and the bmc utilities.  First, login as root:

sudo -i

Now, install the ipmitool:

yum install OpenIPMI ipmitool -y

Start the ipmi service:

service ipmi start

Download the bmc utility:

mkdir -p ~/Downloads/bmc
cd ~/Downloads/bmc
wget -N "http://dinofly.com/files/dell_c1100/bmc-2014-10-15.zip"

If your system is running versions of PERL 5.26 or newer, download this version instead:

# For PERL 5.26+
wget -O "bmc-2014-10-15.zip" -N "http://dinofly.com/files/dell_c1100/bmc-2014-10-15_perl_5.26.zip"

Unzip the bmc tool and make it executable:

unzip bmc-2014-10-15.zip
chmod +x bmc

Here's how to change the BMC interface IP settings:

ipmitool lan set 1 ipsrc static
ipmitool lan set 1 ipaddr x.x.x.x
ipmitool lan set 1 netmask x.x.x.x
ipmitool lan set 1 defgw ipaddr x.x.x.x
./bmc nic_mode set [dedicated|shared]
./bmc allinfo

If the BMC web interace is not responding, try this:

ipmitool bmc reset cold

Running and Debugging Specific WordPress Cron Hooks Manually Using WP-CLI

If your WordPress instance is configured with debugging turned off (WP_DEBUG set to false in wp-config.php) and you need to troubleshoot, debug, or run a specific WordPress cron hook or function manually, you'll find that it's pretty tough to do so.  Fortunately, I found a relatively easy way to do exactly this using WP-CLI.

Install WP-CLI

Install WP-CLI by using the below commands as root:

sudo -i
curl -O https://raw.githubusercontent.com/wp-cli/builds/gh-pages/phar/wp-cli.phar
chmod +x wp-cli.phar
sudo mv wp-cli.phar /usr/local/bin/wp

Now, change into your WordPress instance vhosts directory:

cd /var/www/vhosts/{YOUR_DOMAIN}/httpdocs

Update the above path as necessary.

To run all the scheduled WordPress cron events, use this command:

wp cron event run --all --allow-root

To run a specific WordPress cron hook, use this command:

wp cron event run "NAME_OF_CRON_HOOK" --allow-root

If you need help determining the name of the cron job hook you specifically want to run or debug, install the WP Control plugin in your WordPress instance. Then visit the /wp-admin/tools.php?page=crontrol_admin_manage_page page to see a list of cron hooks and when they run.  Grab the name from the "Hook" column and update your wp cli command to run that cron event!

You can add echo statements and other code to your individual cron function plugins to better debug and troubleshoot them.

OpenVPN Expired CRL – VPN Won't Connect

Recently, I ran into an issue where OpenVPN was no longer working for existing clients.  After looking at the OpenVPN log in /var/log/openvpn.log, I found the following:

VERIFY ERROR: depth=0, error=CRL has expired:

If you see an OpenVPN error about an expired certificate revocation list (CRL), here's how to generate a new CRL:

cd /etc/openvpn/easy-rsa
EASYRSA_CRL_DAYS=3650 ./easyrsa gen-crl
cp /etc/openvpn/easy-rsa/pki/crl.pem /etc/openvpn/crl.pem
chown nobody:nogroup /etc/openvpn/crl.pem
service openvpn restart

Problem solved!

Support Older TLS Versions in Newer Ubuntu / Debian OS Versions

Edit openssl.conf file:

sudo nano /etc/ssl/openssl.cnf

Add this line at the top:

openssl_conf = openssl_init

And add these lines at the end:

[openssl_init]
ssl_conf = ssl_sect

[ssl_sect]
system_default = system_default_sect

[system_default_sect]
CipherString = DEFAULT@SECLEVEL=1

https://askubuntu.com/questions/1233186/ubuntu-20-04-how-to-set-lower-ssl-security-level#answer-1296578

cURL and wget Issues on Ubuntu 16.04

When using wget or curl to make HTTP requests from a no longer supported installation of Ubuntu 16.04 Xenial, if you get any of the following errors:

curl gnutls_handshake() failed: Error in protocol version
curl: (35) error:1407742E:SSL routines:SSL23_GET_SERVER_HELLO:tlsv1 alert protocol version  /home/mohan/mesg
[SSL: TLSV1_ALERT_PROTOCOL_VERSION] tlsv1 alert protocol version (_ssl.c:727) 

The solution is to add SavOS Rob Savoury PPAs to get updated curl and wget packages:

sudo add-apt-repository ppa:savoury1/build-tools
sudo add-apt-repository ppa:savoury1/backports
sudo add-apt-repository ppa:savoury1/python
sudo add-apt-repository ppa:savoury1/encryption
sudo add-apt-repository ppa:savoury1/curl34
sudo apt-get update && sudo apt-get upgrade
sudo apt-get install wget curl python2.7