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Strange network slow down with gentoo-sources -2.6.17-r* and Dell servers

I ran across this with my laptop, then suddenly I started noticing this with my vmware-server. After some hard googling, I came across a post, that stated that windows scaling should be turned off. As soon as I did this.. my speeds were up on the box. Symptoms, were weird.. only wget seemed to be slow. SSH or SCP was fast. So when I was emerging packages at 2-10K it was brutal, normal traffic for my network is 150K.

How to view contents of cert

This was originally from
http://mia.ece.uic.edu/~papers/volans/settingupCA.html

Top view the contents of a .pem cert, you can use openssl

Here is an example and output:

mia#> openssl x509 -in cacert.pem -text -noout
Certificate:
Data:
Version: 3 (0x2)
Serial Number: 0 (0x0)
Signature Algorithm: md5WithRSAEncryption
Issuer: CN=Certificate Authority Created by Shashank Khanvilkar, ST=Illinois, C=US/emailAddress=shashank@evl.uic.edu, O=Root Certification Authority

SEC - simple event correlator for SSH login real-time alerts

I originally was using tenshi, but due to crap support and irritating issues, I opted for something different. I discovered sec, and I'm pretty pumped on it. I'm just scratching the surface, and the first project I wanted to involve sec was a real-time email alert on successful and failed SSH logins.

Currently, my setup only allows connections from trusted networks, so I'm not getting alerts a million times with SSH worms, etc.

Updating certs for Postfix and Courier

I wanted to post a procedure on updating certs for Postfix and Courier POP. I do this and forget, so this will be nice for the next time.

First I delete the 'demoCA' directory

rm -rf /etc/ssl/misc/demoCA

Then I edit the CA.pl script since this may have been overwritten on openssl update.

vi /etc/ssl/misc/CA.pl
add nodes (newca)
print "Making CA certificate ...\n";
system ("$REQ -new -nodes -x509 -keyout " .

How to use 'patch'

So today I was asked how to 'patch' a file with a diff file. My friend found a diff file from the supporting website of his application he needed to update, and he needed to know how to safely apply it.

You can patch by going into the directory that has the file that needs patching. In this case the patch was on a webpage, so he had to copy the contents and create a file

cd /dir/of/app
vi code.patch

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