Thursday, April 17, 2008

blogger fail

Yup, bloggers sftp publishing is terrible. I thought it was UnixShell for a long time as their internet connection plain sucks. When I started to publish to my new colo, I had the same timeout problems.

So this has all been exported to wordpress, and life continues there. Back to 100% self-hosted blogging.

Monday, April 14, 2008

vmware timekeeping part 3

earlier posts here and here.

A review:
1) We removed ntp from the linux guests and left it running on the vmware hosts.
2) We installed open-vm-tools on the guest and live enabled timesync using vmware-guestd

Notes revealed we were gaining about 40s a day.

3) set clock=pit (use clocksource=pit now) in the grub config as a kernel option and restarted a guest



That looks like about 40s over three weeks.

4) today I noticed a lot of "/dev/vmmon[3685]: host clock rate change request 500 -> 998" messages on the vmware hosts (linux) and I set up the recommendations here which is 'host.cpukHz = cpuspeedinkhz', 'host.noTSC = TRUE', and 'ptsc.noTSC = TRUE' to work around possible speed step issues.

I accidentally used khz = mhz * 100 instead of khz = mhz * 1000 which made the time get way off when I stopped and then started the vm I testing was on. This was interesting though because I was afraid I'd have to stop vmware-server, not just an individual vmware-vmx process to get it to re-read /etc/vmware/config.

Looping ntpdate shows about 8/10th of a second gain over 20 minutes. Still more gain than I'd like to see. Will watch the graph and then try again in a week or two.

Friday, April 11, 2008

Avocent KVMoIP LDAP Configuration

The manual is way too confusing about this:

It works like this:
LDAP Overview:
LDAPS works fine with Server 2003 R2 AD, and is preferred (leave it on port 636). If you're using fqdn's, make sure you have DNS servers set in the network section.

On the Search page:
'Search DN/Password' is the Bind DN/Password.
'Search Base' is similarly the 'Base DN'.
'UID Mask' should be 'attribute=%1', replace attribute with the name of the attribute storing the username, so generally with AD this is 'sAMAccountName=%1'

Query page:
If 'Group Container Mask' = 'ou=%1' and Group Container = 'KVM' then we're looking for ou=KVM in the above configured BaseDN. This is where we'll set everything up. I recommend staying at the top of the tree for simplicity.

Target mask should be 'cn=%1' because we're looking for objects and * Access Control Attribute will be 'info' because that corressponds to 'notes' in the ADUC UI.

In this OU container:

1) Create a computer object with the same name as the KVM name under 'Appliance -> Overview'. I renamed this to KVM01. I had to do this on a DC as MMC was crashing on my terminal server when creating a computer object, probably unrelated.

2) Now create a group, call it whatever. In the notes section put 'KVM Appliance Admin'. This is how we define what you can do. Add the KVM computer object to this group, and any users (or groups, ie domain admins) you want.

3) These people will have full access to the kvm and all objects. It sounds like adding access into individual objects requires being in a group with info of 'KVM User' and the computer objects for the actual server names in the group as well. Bah.

Thursday, April 10, 2008

Vista trust relationship login failures

A local Vista computer started having intermittent login failures when a domain user tried to log in about a trust problem with the account database.

Since Vista disables the local administrator account even though it had a password. I used Nordahl's ntpasswd linux boot cd to enable the local administrator account (if I hadn't known the password I could have changed it as well). Of course the CD requires access to the syskey as the SAM is encrypted, but it always finds it automatically since nobody puts the syskey on floppy.

Then I logged in and removed the computer to the domain, changed it's name, and rejoined it and things were fine.

Domain profiles were kept intact by the way.

Thursday, April 03, 2008

FHS Compliance for NFS mounts

Where should one mount shared NFS data?

FHS 2.3 has no advice. All the NFS talk is about how you might NFS mount /usr and the likes.

Options: /opt, /mnt, /srv. mnt is the old school way, but FHS uses the key word 'temporary' which makes sense these days, even though we've started using /media for most things temporary. opt? I stay away from opt since I touched oracle.

/srv : Data for services provided by this system
Sounds good to me. nfs mounts will go in /srv, since it's all data for services provided by this system.