Using TPM in Linux

Nothing for me to add, found a really good guide:

https://www.grounation.org/index.php?post/2008/07/04/8-how-to-use-a-tpm-with-linux

Using stunnel to connect to gmail imaps/pop3s

# Useful for clients/daemons that can't imaps/pop3s.
# Axigen mail server can't migrate imaps mailboxes for example.

# stunnel.conf
sslVersion = SSLv3

socket = l:TCP_NODELAY=1
socket = r:TCP_NODELAY=1

debug = 0
output = /var/log/stunnel4/stunnel.log

client = yes

[pop3s]
accept = 110
connect = pop.gmail.com:995

[imaps]
accept = 143
connect = imap.gmail.com:993

Generate .CSV file of MySQL results

SELECT foo, bar INTO OUTFILE '/some/file.csv' FIELDS TERMINATED BY ',' ENCLOSED BY '"' LINES TERMINATED BY '\n' FROM t1 WHERE ...

iptables NAT port forward

# The port forwarding
iptables -t nat -A PREROUTING -i ethX -p tcp -m tcp --dport 12345 \
-j DNAT --to-destination 10.10.10.10:12345

# The masquerade
iptables -t nat -A POSTROUTING -o ethX -j MASQUERADE

# Don't forget to turn on ip_forwarding:
sysctl -w net.ipv4.conf.ethX.forwarding=1

Self-signed Apache style SSL Certificate

# Generate the key
openssl genrsa -des3 -out myhost.com.key 1024

# Generate the Certificate Signing Request
openssl req -new -key myhost.com.key -out myhost.com.csr

# Generate a Self-Signed SSL Certificate
openssl x509 -req -days 365 -in myhost.com.csr -signkey myhost.com.key -out myhost.com.crt

create a ramdisk for fast read/write access

ramfs grows dynamically, tmpfs doesn't. tmpfs uses the swap if you exceed the size specified, while ramfs doesn't. For an application like varnish, you can set a fixed size of the cache, so it _should_ not be a problem.

# example of mount
mount -t ramfs none /tmp/varnish -o size=1024m

# for fstab
cache /tmp/varnish ramfs defaults 0 0