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Yes, some distros still use rpm.

Extract files from an RPM:

rpm2cpio filename.rpm | cpio -idv

Unpack an RPM into /tmp/deleteme without installing it:

rpm -ivh -root /tmp/deleteme --nodeps --noscripts package.rpm

Install

rpm -ivh

Upgrade (use this except for kernels)

rpm -Uvh

Find out what's installed

rpm -qa

See which package a file belongs to

rpm -qf

List files provided by a package

Get into the correct directory:
cd /etc/pki/tls/certs

Generate key
openssl genrsa -des3 -out mike.key 4096
chmod 600 mike.key

Generate signing request
openssl req -new -key mike.key -out mike.csr
chmod 600 mike.csr

Get the CA to sign the request
openssl x509 -req -days 10000 -in mike.csr -out mike.cert \
-CA /etc/pki/tls/certs/army.ca/Army.ca_CA.cer \
-CAkey /etc/pki/tls/certs/army.ca/Army.ca_CA.key -CAcreateserial

Getting SELinux working can be tough. Here are some commands I found useful.

Show the security context of a file:

ls -lZ

Copy the context from one file to another:

chcon --reference=<source> <destination>

Create a rule from an audit log (contained in /tmp/selinux):

/usr/bin/audit2allow -i /tmp/selinux

Explain an audit log (that appears in dmesg):

/usr/bin/audit2why -d

Reading an audit entry:

To see if yourserver.com is an open relay, you can run through the following sequence on any box that has a telnet client:

telnet yourserver.com 25
HELO myserver.ca
MAIL FROM:
RCPT TO:
DATA
From: "Relay Test"
To: Mike
Subject: Open Relay Test
This is a relay test. A properly configured mail server
should decline to relay this message.
 
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QUIT