[CentOS] Anyway to ensure SSH availability?

Wed Jun 29 21:22:46 UTC 2011
m.roth at 5-cent.us <m.roth at 5-cent.us>

Les Mikesell wrote:
> On 6/29/2011 4:04 PM, Emmanuel Noobadmin wrote:
>> On 6/30/11, Les Mikesell<lesmikesell at gmail.com>  wrote:
>>> The seriously on-the-cheap approach is to run a few virtual servers on
>>> hardware slightly better than one of the individual servers would need.
>>
>> Actually THAT is the fundamental problem ;)
>> The physical server is frankly much more powerful than the two guest
>> running on it. I have the same applications + public web/email running
>> on old dual core machines with less memory than the guests.
<snip>
> OK, but without knowing the cause, you already know the cure.   Make the
> virtual servers not share physical disks - they will always want a
> single head to be in different places at the same time.  And there is
> also probably some ugly stuff about how using files for virtual disk
> images and perhaps LVM on both the real and virtual side makes your disk
> blocks misaligned. Fixing that might help too.

Here's another one, that I got from another admin talking to VMware: watch
out just how many virtual CPUs you assign to each VM. If you've assigned
4, it is actually going to sit there waiting until it gets 4 virtual CPUs.
As of '09, VMware was recommending assigning 2.

        mark