Command Directory
Ethtool
ethtool -p <interface name> Will blink the network light to signify which interface the system actually thinks is “eth0” “eth1” etc.
Java Keytool
keytool -list -v -keystore <jks keystore file> Provides information on the certificate(s) inside a JKS file.
keytool -delete -alias <cert alias> -keystore <jks keystore file> Deletes the certificate that has the specified alias name.
Linux - DNS
dig @<nameserver> <common name> <record type> +short Returns just the IP/data for the record.
Linux - Kernel Information
uname -a Provides general information about the linux kernel, system hostname, etc.
cat /proc/cmdline Provides information on the booted kernel parameters / flags.
Linux - openssl
openssl s_client -connect <remote host>:<destination port - usually 443> Debugs the HTTPS transaction between client and remote host. (Thanks to Zack for this one too).
openssl x509 -noout -in cert.pem -dates Returns the dates that a pem formatted certificate is valid for.
Linux - Process Information
ps -eo pid,ppid,rss,vsize,pcpu,pmem,cmd -ww —sort=pid | grep -i <command that corresponds to process> | grep -iv grep Provides the process details for a specific process that matches the grep search. Details include: process id, parent process id, non-swapped physical memory being used (in kB), swapped memory being used, CPU utilization, physical memory utilization, and command path. Also uses an inverse grep search to eliminate the grep search itself from the output.
Linux - Searching
grep -iv <search string> <file path> Returns case insensitive entries that DON’T match the search string.
Linux - SendMail
for x in `find . -type f -name “qf*” | xargs grep -l invalidaddress@domain.com | cut -b3-`; do y=d`echo $x | cut -b2-`; mv $x /root/loopingmessages; mv $y /root/loopingmessages/; done Search QF header files for an email address, identify corresponding df counter-part, and move both of the files to a looping message directory. (Huge thanks to Zack Train on this one).
Linux - System Info
dpkg-reconfigure tzdata Change system time zone in Ubuntu server.
