Cholesterol Confusion

LDL is the one thing doctors always pay attention to when they do cholesterol blood test.

Too high and they shout you need statins.

The problem is when you are on a low carb diet like Atkins or Protein Power, after a while your triglycerides will be low while your high-density lipoprotein cholesterol (HDL) is high. The problem is LDL is expensive to measure in a laboratory, hence they generally calculate out this value using the Friedewald estimation.

ie, LDL-C (calc.) = CH − HDL − (TG/5)^2.

However this formula only works for triglycerides under 400mg/dl (4.52 mmol/l) and more importantly above 100mg/dl ( 1.13 mmol/l). When triglycerides are  above 400mg/dl, the labs generally warn in the report that it cannot be calculated. But then don’t warn if its below 100mg/dl.

The problem is that if you are on low carb diet for a while, your triglycerides will naturally fall below 100mg/dl. Then then abnormal LDL will be inflated by as much as 58%.

Hence the Cholesterol Confusion

For better estimates you would use the Iranian formula from this medical paper.

Or better ask for a direct LDL measurement

Do note that you can only use this formula if TG < 100mg/dl (1.13 mmol/l) AND TC > 250mg/dl (6.46mmol/L)

For mmol/L you would use

LDL (mmol/L) = TC/1.19 + TG/0.81 – HDL/1.1 – 0.98

For mg/dL

LDL (mg/dl) = TC/1.19 + TG/1.9 – HDL/1.1 – 38

If a doctor tries to press you to use Statins, please ask him to refer to the following articles

For the doctor:

Low Triglyceride Levels Affect Calculation of Low-Density Lipoprotein Cholesterol Values

The impact of low serum triglyceride on LDL-cholesterol estimation

The accuracy in using modified Friedewald equation to calculate LDL from non-fast triglyceride: a pilot study

For us layman:

Low-carbohydrate diets increase LDL: debunking the myth

Making Dr Friedewald an honest man

PowerDNS Munin Plugin

PowerDNS Munin Plugin not working.

Running PowerDNS Munin plugins from linux shell command line works fine.

Running from “munin-run” works fine as well.

But doing a “telnet localhost 4949” and “fetch <pdns_graph_script>” returns nothing.

it turns out that munin-node (from munin-node.log) does not have access to the pdns socket

2016/03/17-23:40:03 [14820] Error output from pdns_errors:
2016/03/17-23:40:03 [14820]     Fatal error: Unable to connect to remote ‘/var/run/pdns.controlsocket’: Permission denied

Most cases for Munin problems are usually permission problems when it is munin-node is being invoked.

Munin-node is running as user munin group munin. It usually does not have permissions to access various applications especially those that are run exclusively as another user. For example, iptables and access to sockets.

The solution is to ensure that Munin-node can shift its own permission for a short time while running the plugin.

Sometimes it can be caused by Selinux running. See this article.

Another possibility is that your default bash shell either does not have the correct paths to various binaries listed. Here you can either hardcode the paths or ensure your paths are part of your script. See this article.

Solution:

You need to add a file in /etc/munin/plugins.conf.d/pdns

[pdns_*]
user root

You have to restart munin-node for it to take effect. Either via “service munin-node restart” or “systemctl restart munin-node”

Linux request_module: runaway loop modprobe binfmt-464c

On Bootup:

request_module: runaway loop modprobe binfmt-464c

request_module: runaway loop modprobe binfmt-464c

request_module: runaway loop modprobe binfmt-464c

request_module: runaway loop modprobe binfmt-464c

Reason:

This usually means you are trying to boot using a 32bit kernel but your installation is 64bit or viceversa.

If you boot a 32-bit kernel with a 64-bit OS, when the kernel tries to start /sbin/init (a 64-bit binary), it won’t recognize the binary format, and it’ll try to load the binfmt-464c kernel module, which is ELF support. (ELF support is generally compiled into the kernel, not built as a module, by the way.)