OpenSSL Cheat Sheet

Create a strong CSR and private key openssl req -new -nodes -newkey rsa:4096 -out server.crt -keyout server.key Parsing out the data within a certificate openssl asn1parse -in server.crt Checking a certificate/key modulus to see if they correspond openssl rsa -in server.key -modulus -noout | openssl md5 openssl x509 -in server.crt -modulus -noout | openssl md5 Convert a key […]

/dev/null not found?

Today I came across a box with no /dev/null. Disturbingly that box even refused to boot. Here’s a quick fix in case: Boot with some liveCD and chroot or use some emergency shell and kill the defect dev file in case it’s still there and regenerate: rm -rf /dev/null mknod /dev/null c 1 3 chmod 666 /dev/null

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