HomeLab: How to Resolve Supermicro x8dti Fan Revving Issues

Supermicro-Hyper-Speed-6027AX-TRF-Front-Straight

Its Winter here in the Atlanta area, and the temperatures have been dropping down close to freezing. Likewise, the temperatures in my basement Homelab have been dipping below 66 degrees Fahrenheit, and apparently this makes my Supermicro Servers a bit unhappy.

A bit of background. When I set out to build my lab I decided to transfer my Supermicro X8DTI boards out of their stock rack mount enclosures (like what you see above) and into Standard EATX Towers. Running my boards in these towers allowed me to use large 120mm and 140mm fans for cooling. Sound wise this is a huge improvement over the stock 80mm fans used in the default enclosure as these larger fans can spin much slower than stock and still keep the system cool.

On several occasions I have been working in my office and have heard the fans in my lab servers revving up and back down again. At first I thought that maybe a fan was failing, and that one of my systems was overheating. Or that one of my systems had sucked in a bit too much basement dirt and dust. However neither were the case.

Specifically what was happening was this… The systems were running cool, so the fans would spin down to a low rpm and the system would then throw a low rpm threshold alert and spin the fan back up.When this occurs the system switches into some sort of “Critical Cooling Mode” and spins all the fans up to 100% for a few seconds. Rinse and repeat a few dozen times and you hear what almost sounds like an intoxicated neighbor playing with his new weedeater.

Using the IPMIitool command from my Linux desktop first logged into IPMI controller on my systems and checked to make sure that the fans were actually working properly. SDR is short for Sensor Data Repository

# ipmitool -H 10.1.0.104 -U admin -P <password> sdr list
Fan2 | 2176 RPM | ok
Fan3 | 340 RPM | ok
Fan4 | no reading | ns
Fan5 | 544 RPM | ok
Fan6 | 340 RPM | ok
…truncated…

Fan6 above is spinning mighty slow. Slow enough to drop below the Lower Non-Critical Value threshold. Rather than increase the speed of the fan as I have seen others do, I decided to lower the thresholds for this fan with the command below. Since Fan5 is also a bigun’ I decided to preemptively adjust its thresholds as well.

ipmitool -H 10.1.0.104 -U admin -P <password> sensor thres Fan4 lower 100 200 300
ipmitool -H 10.1.0.104 -U admin -P <password> sensor thres Fan5 lower 100 200 300

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Redhat Satellite 5: How to Clone Security Errata to a Software Channel

space_dogFirst check to see if the errata is available to your local satellite server. To accomplish this log into your organizations satellite server and click on the “Errata” tab. Then on the left side of the page click on “Advanced Search”.

In the search box enter the RHSA number (Redhat Security Advisory Number) for the errata that you want to clone/update. In this example I am searching for RHSA-2014:1924, which is a Thunderbird security update.

If your search does not return any results, you will need to manually sync your local Satellite Server with Redhat.To accomplish this you need to ssh into your local satellite server and run the command shown below. Note that this does not update any packages/errata. This does update the list of availbile packages/errata.

/usr/bin/satellite-sync
[root@myserver ~]# satellite-sync –email
10:08:09 Red Hat Satellite – live synchronization
10:08:09 url: https://satellite.rhn.redhat.com
10:08:09 debug/output level: 1
….truncated….

Once you are able to locate the specific fix in via “Erratum Search” you may proceed to the next step. In this example, as I stated above, I am searching for RHSA-2014:1924.

clone_erratta

Now that our local Satellite server is aware of our specific errata, click on “Clone Errata” on the left side of the page. Search the page “Errata Management” for the specific fix that you want to apply. Note that the “Errata Management” page does have built in search functionality — don’t ask me why — so you must search using your browser’s own page search function.

clone_thunderbird

Once you have located the correct Security Advisory, put a check in the box and spend about 5 minutes scrolling down to the bottom of the page. Stop when your arm is tired, or once you locate the “Clone Errata” button. Obviously you want to click this.

Note that your newly added and updated errata/package may not become immediatley availible to install. You nay need to run the following commands to refresh/reload your repos.

#yum clean all

Then check for updates with the command below.

#yum check-update

Yum: Under the Covers with GPG Keys

Skeleton_key_1_keychain_sculpture_photo_cut_outs-r558fef9b275d4609b522ac07970a6af6_x7sa6_8byvr_324Hey look at this spooky key. Don't be frightened little one. Nothing scary is going to happen to you here. This is a safe place. As a matter of fact, if you stick around you might just learn a thing or two. A thing or two about GPG!

First off do any of us really know what GPG stands for? Well yes we do! It stands for GNU Privacy Guard. RPM Package creators use GPG to apply a digital signature to their packages. If a package was tampered with, then its GPG signature will no longer match what was placed in the original package.

First off to check what keys you have installed on your Linux server you can run the following rpm command as show in the example below.

[root@ip-172-31-22-45 ~]# rpm -qa gpg-pubkey
gpg-pubkey-0608b895-4bd22942
gpg-pubkey-fd431d51-4ae0493b
gpg-pubkey-2fa658e0-45700c69

 

Neet I have three keys installed. But lets say want to install another one. Well I can do so with the command below. In this example I have navigated to /etc/pki/rpm-gpg and am going to install the redhat beta key on my server.

[root@ip-172-31-22-45 rpm-gpg]# rpm –import RPM-GPG-KEY-redhat-beta

Hey that was fun. Now lets get our hands a bit dirtier.

Want to get more information on a specific key. Then this command is your huckleberry. Here you can see that this is the pubkey for the EPEL repo.

[root@ip-172-31-22-45 rpm-gpg]# rpm -qi gpg-pubkey-0608b895-4bd22942
Name        : gpg-pubkey                   Relocations: (not relocatable)
Version     : 0608b895                          Vendor: (none)
Release     : 4bd22942                      Build Date: Sat 14 Jun 2014 09:13:58 AM EDT
Install Date: Sat 14 Jun 2014 09:13:58 AM EDT      Build Host: localhost
Group       : Public Keys                   Source RPM: (none)
Size        : 0                                License: pubkey
Signature   : (none)
Summary     : gpg(EPEL (6) <epel@fedoraproject.org>)
Description :

 

To verify signature of a downloaded package, use the rpm command as shown below. In this example I have highlighted the key that was used to sign this package.

# rpm -vK nautilus-dropbox-1.6.0-1.fedora.i386.rpm
nautilus-dropbox-1.6.0-1.fedora.i386.rpm:
    Header V3 RSA/SHA1 Signature, key ID 5044912e: OK
    Header SHA1 digest: OK (a4d51906633f92913db075ba33946f50999c245e)
    V3 RSA/SHA1 Signature, key ID 5044912e: OK
    MD5 digest: OK (1b8ff7abc18f68bf274e24fc57fd3a87)

 

Using the bolded information in the example above, I can then use this information to track down the exact key that was used to sign the package.

[root@localhost Downloads]# rpm -qa | grep 5044912e
gpg-pubkey-5044912e-4b7489b1

 

Is this awesome, well not really, but you never know when you might need to use this information. Like on a test. Wink Wink.

Related articles

Using Yum Update to Apply Security Patches Only
How to Enable EPEL Repository on CentOs for Yum
Signing rpm packages with GPG

RPM Package Inspection for Fun and Profit

6a00d8341c562c53ef01538f8abd65970b-800wi"Whats in the box" — David Mills

Lets face it, one of your users needs to have a package installed on a system, you tend to do it for them. That is, as long as the package looks safe. Sure, your not going to install an rpm that is clearly dangerous, but as long as the package name looks reasonable and you trust the user, you might actually just go ahead an install it for them without thinking much about it. Hell, I know that I have done the exact same thing from time to time. And I have done it with an unsigned package.

"Sure you need this Oracle thing installed on this database server?"

 "You got it directly from Oracle right?"

But honestly, this is a very bad practice as you have no idea what the RPM is installing, and what its pre and post scripts might be doing to your system. Using the command below, you can inspect a packages post and pre install scripts to see if they are doing anything funny. In this instance I am taking a look at the dropbox package for my little Eeepc.

[root@localhost ~]# rpm -qp –scripts /root/Downloads/nautilus-dropbox-1.6.0-1.fedora.i386.rpm

If you have already installed a package and want to see what its pre and post install scripts did. You can run the command above using the installed package name. Note that you will drop the "P" from the command. See my sendmail example below.

[root@localhost ~]#rpm -q –scripts sendmail-8.14.8-2.fc20.i686

 

In addition to checking the pre and post scripts, you also want to check to see if the rpm has any triggers. What are triggers you ask? Well they are extensions to the normal install scripts, and they may often call for the installation of another package or the execution of a command. Just look at all the triggers that fire when you install sendmail.

[root@localhost ~]# rpm -q –triggers sendmail-8.14.8-2.fc20.i686
triggerun scriptlet (using /bin/sh) — sendmail < 8.14.5-3
/usr/bin/systemd-sysv-convert –save sendmail >/dev/null 2>&1 ||:
/bin/systemctl enable sendmail.service >/dev/null 2>&1
/bin/systemctl enable sm-client.service >/dev/null 2>&1
/sbin/chkconfig –del sendmail >/dev/null 2>&1 || :
/bin/systemctl try-restart sendmail.service >/dev/null 2>&1 || :
/bin/systemctl try-restart sm-client.service >/dev/null 2>&1 || :
# workaround for systemd rhbz#738022
/bin/systemctl is-active sendmail.service >/dev/null 2>&1 && \
        ! /bin/systemctl is-active sm-client.service >/dev/null 2>&1 && \
        /bin/systemctl start sm-client.service >/dev/null 2>&1 || :

Obviously you also want to check to see what files are actually part of a package. This can be accomplished with the query and list arguments seen below. Add the "P" argument if the rpm is not already installed. In this case I have already installed sendmail, so I exclude the "P" from the command.

 

[root@localhost ~]# rpm -ql sendmail-8.14.8-2.fc20.i686
/etc/NetworkManager/dispatcher.d/10-sendmail
/etc/mail
/etc/mail/Makefile
/etc/mail/access
/etc/mail/access.db
/etc/mail/aliasesdb-stamp
/etc/mail/domaintable
/etc/mail/domaintable.db
/etc/mail/helpfile
/etc/mail/local-host-names
..truncated…

 

So whats the moral of the story here. Well its really not that hard to take a minute and look under the covers and make sure that the packages that you are installing are not harming your systems. Is definetly worth 5 minutes of your time. Might just save your behind.

 

Related articles

RHEL6 – Simple Postfix Configuration
RHEL6 – Common Postfix Server Roles
Configure sendmail as a client for SMTPs
Sendmail Server

RHEL6 – RTFM Apache Web Server

King-James-BibleThere is a lot to know and remember about configuring Apache as you may or may not have seen from the numerous posts I have written on the subject, and the reality is that no one is going to be able to memorize each and every settings, configuration, and directive. Sure you can bing it or google it , you can even alta-vista it, but only if you have internet access at the time, however there is always a chance that you might get some bad information. So why not refer to the official httpd documentation. You know RTFM and what not.

By and large the best bet for HTTP documentation is the http-manual package that can be installed via yum. It installs to /var/www/manual

# yum -y install httpd-manual

Now one bit of information to note. The documentation installed via the httpd-manual package are in html format, so it not advised that you try to view it with an editor like vim or emacs.  You are going to need an text based web browser like lynx or elinks. I prefer lynx in this situtation, so lets install it.

# yum -y install lynx

Now you can peruse the documentation  as you see fit using lynx.

# lynx /var/www/manual/howto/auth.html

Below are some of the better and more often useful docs that I think that could be found useful in a crunch. Note our base directory is /var/www/manual

  • vhosts/named-based.html – which outlines configuring named-based virtual hosts
  • ssl/ssl_howto.html – which outlines has a nice section on HTTP Basic Authentication.
  • howto/cgi.html – which nicely documents creating a custom cgi directory
  • howt0/auth.html – more on HTTP Auth using htpasswd

Yup thats a lot of very good documentation right there, and its actually written by the people who wrote apache, not some 13 year old kid taking his first shot running apache on Ubuntu.

Installing Spotify on Fedora

Spotify-logo So Spotify is finally available in the US, which is good news for those who are getting tired of Pandora. Hell, Pandora played Celine Dion on my Hardcore Punk Radio Station the other day…wtf.

So anyway, I decided to sign up and was disappointed to find that they did not have an official linux client, However they do publicize an Ubuntu client here, however, since I run Fedora this is not much interest to me.

Thankfully the Europeans have already figured out how to get Spotify running on other linuxes natively, and google found this link on installing the Debian packages on Fedora 13. I am glad to report that these instructions also work on Fedora 12. So far so good on Fedora 12.

However i decided to explore their repo a bit and found that in fact they do have rpm packages. Check out the link below. Sneaky.

http://repository.spotify.com/fedora/

I bit more googling found me this link which contains instructions on installing via the apparently secret rpms.

Btw, if you are a jackass and want to run Spotify under Wine for some reason, click here for instructions.