Bart Silverstrim's questions

While testing some remote DC's, "repadmin /replsummary" ended with an error of

   Experienced the following operational errors trying to retrieve replication information:
       58 - mydc1.mydomain.com
       58 - mydc2.mydomain.com

Information for "Source DSA" for mydc1 and mydc2 both show up with 0 fails/errors; the information is lacking under Destination DSA. This domain controller I ran the command on (remotedc1) can see mydc1 and mydc2.

Pinging from remotedc1 to mydc2 and mydc1 shows an average time of 43ms...

What causes this kind of error?

I want to clear up some confusion and clarify understanding on EC2 instances being EBS backed.

If you start an AMI from a community image, configure your server as you want it configured, then use the "create image" option from the EC2 dashboard to create a snapshot, that snapshot (image) can be used to create more servers with your configuration and is considered EBS-backed, yes?

If you create a snapshot and later terminate your AMI EC2 instance, that machine goes away, but the snapshot persists and can be used to recreate your instance, whereas if you don't create an image you lose everything upon termination?

And if you created your server, created an image/snapshot, then terminated your running instance and created a new EC2 instance from your snapshot, then do your changes persist upon termination (new data gets saved to the snapshot) or does it revert to your snapshot's saved state unless you create a new snapshot?

Creating the image/snapshot (these are the same thing with their terminology, yes?) means the resulting disk image is stored on S3, it just doesn't show up under S3 buckets, correct? So the data will be saved across multiple sites for redundancy invisibly?

I think I know the answer to these, but I'd like to verify it.

Similar questions have been asked but I need to know what would be recommended under the circumstances, to know if I'm missing something in my understanding of using EC2.

A small startup is running their business on the EC2 network and asked me for some advice on backup options. They're self-funded at the moment and are doing what they can to save costs when it's feasible. Without delving too much into the configuration of their systems, I'll give a web server as an example; it's a simple web server with a database. The rub is that they do not want the server taken down.

The person that has been doing the setup believes that they should either just do periodic dumps of the database and store that on S3, or create scripts that would rebuild a new server on Amazon when they're needed by backing up select folders holding configuration information. He suggested that to create snapshots of the server would be wasteful, as they take a lot of disk space and essentially there would be data rot between large data dumps so the snapshot would become outdated quickly.

My thought was to take a snapshot of the VM, and then do periodic dumps of the database and store in S3. If they were to lose the EC2 instance or have something like an update render it unusable, they could use the snapshot to build the server back up relatively quickly with the latest database dump, rather than start from scratch to build a new instance from a completely new AMI.

My understanding is that taking a snapshot of an EC2 instance (or EBS store) will require downtime, something they are hesitant to have. I also have read that you should have the server shut down to keep the filesystem consistent when the snapshot it taken. Since they do not have a cluster behind a balancer yet, these limit the options involving snapshots.

Scripting to build servers, unless there is something specific to Amazon I'm unaware of, would involve creating a Chef or Puppet server that could deploy new servers with their associated roles on EC2. Right now the startup doesn't have funding for keeping that kind of server in the wings and they, right now, don't really need to deploy that many servers.

Ideally they would have the funding to create a number of servers behind a virtual balancer or Amazon's balancer service, then take down the servers one at a time to perform updates or snapshots. Right now I'd be nervous at the idea of doing updates because if you're doing dumps of the database, that won't help if a system update alters a library on which their application relies and the service goes down.

I also supposed another option is to run a script that creates an EBS volume, mounts it, and on the server run something like rsync to capture most of the filesystem information to the EBS volume then compress and copy the contents to S3, disconnect the volume and destroy it to save storage cost, then do a database dump to catch in-flight data that would be inconsistent otherwise. For some of their servers it will most likely become necessary to save to temporary EBS volumes as their database needs grow.

A VMWare sandbox is being created to recreate their network systems in an environment where updates can be pre-tested before applying them to the production systems on Amazon. I am hoping that would minimize the possibility that a system update will kill their application.

So...given the restrictions of running one server, with database and application server on the system, looking to have as close to no downtime as possible (restricting the use of snapshots and having the backup process be as "hot" as possible (created live without taking the server down), am I on the wrong track for suggesting scheduling a time to create a snapshot of the EC2 instance in it's working state and from there doing database dumps to copy to S3? Is there a better strategy to pursue in creating a live backup of a server if snapshots will create downtime?

I'm just getting the hang of trying to configure/use Windows Deployment Services (WDS) to image Windows 7 workstations on our network.

I have the WDS server configured so any machine can request an image, but the administrator must authorize the configuration. This way we would minimize accidental (or malicious) re-imaging of computers on the network.

For the initial setup, I configured the base Windows 7 install and boot images then hooked up a testbed Dell machine. Booted the Dell with PXE boot, it started the PXE boot, and went back to the WDS server to authorize ID 1 machine. No problem, the Dell booted to Win7 setup and started the whole configuration process.

Got all done and started going through instructions to create an image WIM file on the master; Sysprep with the generalize option completely hosed the staging client. After many profanities, I decided to start from scratch again.

Rebooted the client with PXE boot, and this time it saw the WDS server and started the re-imaging process again without me authorizing it.

This makes me think that if individuals on the network managed to PXE boot an imaged machine, the machine will allow them to re-image it without authorization.

Is this the case?

If so, is there a way to clear out the already authorized ID's/MAC's from the WDS server?

Using Windows Deployment Services on Windows 2008 Server.

DPM 2007

Server with issue is Windows Server 2003 R2 Enterprise Edition

DPM is reporting that "DPM encountered an error while performing an operation for C:\program files\vexira antivirus\server\temp\aa29n3f0.vbt (ID 2033 Details: The parameter is incorrect (0x80070057))"

The problem is that the file isn't there and I am not finding any open file handles referring to that file as being held open (did a search using procexp.exe for handles or dll strings).

The temp subdirectory did have misordered permissions when I checked them, but I told Windows to reset the permissions and verified that applications should have access to the subdirectory and it no longer complained about access issues.

Anyone else run into this issue before with DPM?

When users need a username changed, is there a set of places to have to check that the bases are covered?

I know that AD uses a SID to actually identify users, but in this example we have a user that got married and changed her name. Our usernames are first initial last name (jdoe) and so I need to make sure they can log in with their new usernames.

I'm thinking that in AD the only things I have to change are

In general tab, last name, display name, email

In account tab, user logon name, user logon name pre-windows 2000.

In the email addresses tab, add smtp aliases to the new name. I'm not sure if I could delete the old email addresses from here because I'm not sure how Exchange would act with the mailbox, so maybe I'm better off leaving the old address available as well?

Anything I'm overlooking?

Question; we have been trying to get a new printer server configured, and with the organization starting to move into the Windows 7 wagon and mixing 32 bit legacy (XP) systems with 32- and 64- bit Win7 systems, we needed to get specs in place for the printer server (Windows server, active directory, virtualized on VMWare ESXi).

We were told that we would need a 32 bit Windows server to handle the 32 bit machines and their printers, and a 64 bit server for the Win7 64 bit clients. Is this true? I didn't think that sounded right, but have others had experiences that confirm this?

Okay, here's something fairly weird. I'll try to outline the story in a way that makes sense.

We had an old print server (windows 2003 based). We had some issues with people not being able to add printers, and as we added Win7 systems (64 bit) we were going to need other printer drivers added, so we decided we'd do a new printer server to see if that would solve some of the permission errors we were seeing and hopefully clean up some of the issues we were seeing, maybe un-munge some of the drivers.

We called in some guys from a contracting group to rebuild it for us. They built a new virtual machine, installed and updated Windows 2003 server, and used a utility that basically took the configuration of the printers on the old server and migrated them over to the new one. Renamed the old printer server "printers-old" and put the new one in place with the same IP and name as the old printer server.

We get a call from a department saying "we can't print to our 2600n color laserjet."

Boss looks at it, sees that it's not on the server. Odd, it didn't migrate over apparently when the group worked on the servr. He added it to the print server, sends a test sheet from the server, prints fine. Has the client try printing. Nothing comes out.

The print job looks like everything works. Appears in the queue, disappears, Windows says everything went fine (Windows XP, all updates). No errors pop up.

It's not just user A's machine, though. There are apparently two other people that can't print to it either.

In the course of troubleshooting (hope I remember all I've tried here...), I've:

A) deleted and re-added the printer off the network share.

B) Deleted and re-added the "local" network port (HP jetdirect IP port)

C) Deleted all instances of the 2600n from the computer. Re-added. Won't print.

D) Deleted the driver from the local system and re-installed drivers from HP.

E) Added the printer as both a network shared printer off the server and as a local IP printer. Neither works.

F) Added the printer to my workstation for testing (Ubuntu), printing direct to the IP. Printed a test sheet!

G) Picked up a newly imaged machine and updated XP on it. Added the printer from the printer server share. Send test sheet. Nothing came out. This system never had an actual printer installed on it before, and was just added to the domain, so it wasn't "contaminated" with driver/dll issues.

H)Changed the driver to generic text. Didn't work. Changed the driver to a one-off, the 2500 series, nothing printed. In the process of changing these drivers, the spooler actually crashed on the client. @#%!

I) checked connectivity. Client machine can ping the printer fine.

J) updated printer firmware. Latest from HP for the 2600N is from 2007. It restarted (the printer) and came up fine, but still Windows machines won't work.

K) test pages from the server itself work.

L) reinstalling drivers from HP, of course. The 2600N apparently doesn't have options like PCL versions or PS. Just one version. Is the 2600 like some hybrid win-printer?

M) Turned on "printers-old" server, on the "blank slate" testbed I deleted \printers\2600n share, added printer "\printers-old\2600n". Tried printing to it...NOTHING.

N) changed printer settings (turned off bidirectional printing, change print processor settings, etc.)

Errors-nothing pops up. If you didn't check the logs, all seems fine except that nothing ever comes out! BUT if you look at the logs, here's what I had:

source print

event ID 6161

type error

The document Test Page owned by Your_Name failed to print on printer <2600n>. Data type: RAW. Size of the spool file in bytes: 0. Number of bytes printed: 0. Total number of pages in the document: 1. Number of pages printed: 0. Client machine:. Win32 error code returned by the print processor: 0. The operation completed successfully.

The error shows up on the print server if I'm printing to \share, and on the local client if I added the printer as a "local" printer and tried sending to that.

Ordinarily I'd think it was something corrupted on the client, but it happened RIGHT after the new print server was added and printers were migrated, and it immediately affected multiple clients. More than that, this isn't the only printer; we know of one other, a 1022 I believe, that also stopped working with similar symptoms, but I've been focusing on this printer with this particular client (and testbed machine) to keep from losing complete track of what I'm doing to try fixing the issue. I also noticed that these two printers did NOT automigrate over with their utility to the new printer server, and find it odd that the old print server, whose only settings that I know of being changed were the name and IP address, can't be used by the testbed system to add the printer and print like it used to.

The next step we're pursuing is to connect it physically to this person's machine with a USB cable to see if it'll print with that. Other than this, I'm stumped. The consultants have no clue what could have happened or why it's doing this. Anyone have any ideas? Ever run into something like this before?

EDIT- Okay, more info. Another user's system wasn't printing there, and the user told me that User B never had that particular 2600 installed. Turned out she was the only one that never did, everyone in the office other than User B had it. So on a lark, I remoted to B's system, navigated to the printers-old server, and added the 2600. It worked.

I then went back to User A's system, and logged in as an administrative user, deleted the driver from the local computer (printer server settings from the printers configuration window), and deleted all instances of local/shared 2600 printers. Then I navigated to printers-old, added the printer from there. Test sheet printed!

So...something weird with the new printer server's drivers that is screwing it up? Again, this started with the migration and the fact that this printer and the 1022/1020 series printers never migrated with their utility...hmm...

Obviously this is a workaround issue for now since we want to retire the printers-old server. But this is still strange to me as to why the printer on User A's system wouldn't print with the printer installed as a local IP printer nor would it print to the printers old system until I purged the driver AND went directly to the old server. Looks like a printer driver corruption issue that spreads from the new server and doesn't go away just by deleting the printers on the client; the client gets tainted by trying anything with the new printer server?

Here's the issue...we have a network with a lot of Cisco switches.

Someone plugged in a hub on the network, and then we started seeing "weird" behavior; errors in communication between clients and servers, or network timeouts, dropping network connections, etc. It seemed that somehow that hub (or SOHO switch) was particularly freaking out our Cisco 3700 series switches.

Disconnect that hub or netgear-type SOHO switch and things settled down again.

We're in the process of trying to get a centralized logging server for SNMP and management, etc., to see if we can trap errors or narrow down when someone does this sort of thing without our knowledge because things seem to work, for the most part, without issue, we just get freaky oddball incidents on particular switches that don't seem to have any explanation until we find out someone decided to take matters into their own hands to expand available ports in their room.

Without getting into procedure changes or locking down ports or "in our organization they'd be fired" answers, can someone explain why adding a small switch or hub, not necessarily a SOHO router (even a dumb hub apparently caused the 3700's to freak out) sending DHCP request out, will cause issues? The boss said it's because the Cisco's are getting confused because that rogue hub/switch is bridging multiple MAC's/IP's into one port on the Cisco switches and they just choke on that, but I thought their routing tables should be able to handle multiple machines coming into the port. Anyone see that behavior before and have a clearer explanation of what's happening?

I'd like to know for future troubleshooting and better understanding that just waving my hand and saying "you just can't".

Here's a show run

Current configuration : 25591 bytes

!

version 12.2

no service pad

service timestamps debug datetime msec

service timestamps log datetime msec

service password-encryption

!

hostname ###########

!

boot-start-marker

boot-end-marker

!

enable secret 5 ############

!

!

!

no aaa new-model

switch 1 provision ws-c3750g-24ps

switch 2 provision ws-c3750-48ts

switch 3 provision ws-c3750-48ts

switch 4 provision ws-c3750-48ts

switch 5 provision ws-c3750-48ts

system mtu routing 1500

authentication mac-move permit

ip subnet-zero

ip routing

!

!

!

mls qos map policed-dscp 24 26 46 to 0

mls qos map cos-dscp 0 8 16 24 32 46 48 56

mls qos srr-queue input bandwidth 90 10

mls qos srr-queue input threshold 1 8 16

mls qos srr-queue input threshold 2 34 66

mls qos srr-queue input buffers 67 33

mls qos srr-queue input cos-map queue 1 threshold 2 1

mls qos srr-queue input cos-map queue 1 threshold 3 0

mls qos srr-queue input cos-map queue 2 threshold 1 2

mls qos srr-queue input cos-map queue 2 threshold 2 4 6 7

mls qos srr-queue input cos-map queue 2 threshold 3 3 5

mls qos srr-queue input dscp-map queue 1 threshold 2 9 10 11 12 13 14 15

mls qos srr-queue input dscp-map queue 1 threshold 3 0 1 2 3 4 5 6 7

mls qos srr-queue input dscp-map queue 1 threshold 3 32

mls qos srr-queue input dscp-map queue 2 threshold 1 16 17 18 19 20 21 22 23

mls qos srr-queue input dscp-map queue 2 threshold 2 33 34 35 36 37 38 39 48

mls qos srr-queue input dscp-map queue 2 threshold 2 49 50 51 52 53 54 55 56

mls qos srr-queue input dscp-map queue 2 threshold 2 57 58 59 60 61 62 63

mls qos srr-queue input dscp-map queue 2 threshold 3 24 25 26 27 28 29 30 31

mls qos srr-queue input dscp-map queue 2 threshold 3 40 41 42 43 44 45 46 47

mls qos srr-queue output cos-map queue 1 threshold 3 5

mls qos srr-queue output cos-map queue 2 threshold 3 3 6 7

mls qos srr-queue output cos-map queue 3 threshold 3 2 4

mls qos srr-queue output cos-map queue 4 threshold 2 1

mls qos srr-queue output cos-map queue 4 threshold 3 0

mls qos srr-queue output dscp-map queue 1 threshold 3 40 41 42 43 44 45 46 47

mls qos srr-queue output dscp-map queue 2 threshold 3 24 25 26 27 28 29 30 31

mls qos srr-queue output dscp-map queue 2 threshold 3 48 49 50 51 52 53 54 55

mls qos srr-queue output dscp-map queue 2 threshold 3 56 57 58 59 60 61 62 63

mls qos srr-queue output dscp-map queue 3 threshold 3 16 17 18 19 20 21 22 23

mls qos srr-queue output dscp-map queue 3 threshold 3 32 33 34 35 36 37 38 39

mls qos srr-queue output dscp-map queue 4 threshold 1 8

mls qos srr-queue output dscp-map queue 4 threshold 2 9 10 11 12 13 14 15

mls qos srr-queue output dscp-map queue 4 threshold 3 0 1 2 3 4 5 6 7

mls qos queue-set output 1 threshold 1 138 138 92 138

mls qos queue-set output 1 threshold 2 138 138 92 400

mls qos queue-set output 1 threshold 3 36 77 100 318

mls qos queue-set output 1 threshold 4 20 50 67 400

mls qos queue-set output 2 threshold 1 149 149 100 149

mls qos queue-set output 2 threshold 2 118 118 100 235

mls qos queue-set output 2 threshold 3 41 68 100 272

mls qos queue-set output 2 threshold 4 42 72 100 242

mls qos queue-set output 1 buffers 10 10 26 54

mls qos queue-set output 2 buffers 16 6 17 61

mls qos

!

!

!

!

!

spanning-tree mode pvst

spanning-tree etherchannel guard misconfig

spanning-tree extend system-id

!

vlan internal allocation policy ascending

!

!

class-map match-all AutoQoS-VoIP-RTP-Trust

match ip dscp ef

class-map match-all AutoQoS-VoIP-Control-Trust

match ip dscp cs3 af31

!

!

policy-map AutoQoS-Police-CiscoPhone

class AutoQoS-VoIP-RTP-Trust

set dscp ef

police 320000 8000 exceed-action policed-dscp-transmit

class AutoQoS-VoIP-Control-Trust

set dscp cs3

police 32000 8000 exceed-action policed-dscp-transmit

!

!

!

!

interface GigabitEthernet1/0/1

switchport trunk encapsulation dot1q

switchport trunk native vlan 11

switchport mode trunk

spanning-tree portfast

!

!

!

interface GigabitEthernet5/0/1

!

interface GigabitEthernet5/0/2

!

interface GigabitEthernet5/0/3

!

interface GigabitEthernet5/0/4

!

interface Vlan1

ip address ############## 255.255.0.0

!

ip classless

ip route 0.0.0.0 0.0.0.0 ##############

no ip http server

no ip http secure-server

!

!

ip sla enable reaction-alerts

!

!

!

line con 0

line vty 0 4

password 7 ############

login

line vty 5 15

password 7 ############

login

!

end

Network is running a number of Mac's with Snow Leopard and having issues with DNS resolution (running Windows Active Directory environment with Windows DHCP handing out leases). Is there a way to get the Mac to force registration of the system name with the DNS server (or some way to get DHCP to register the name with the DNS server) the way Windows can be forced to do so with "ipconfig /registerdns"?

Is there something inherent to the way Windows does DHCP/DNS that isn't quite standard?

I have a user with a typo'd name. For the sake of explanation, I'll say the username is lusername, first name Lindsay. Active Directory had the user initially named Lindsey Username, and I need it to be Lindsay Username. As you can tell this doesn't affect the actual login name of lusername.

If I go into Active Directory Users and Computers and search for lus, her name comes up.

I open the properties, and I can change the first name and display name fields, but I can't change the initial name at the top of the "general" tab.

Is there a way to "fix" this without resorting to recreating the user?

I was asking recently about options for divvying up access to file servers, as we have a NAS solution that gets fairly bogged down when our users (with giant profiles, especially) all log in nearly simultaneously. I ran across Gluster and it looks like it can cluster different physical storage media into a single virtual volume and share it out like a virtual NAS from the client perspective and it support CIFS.

My question is whether something like this would be feasible to use for home and profile directories in an active directory environment.

I was worried about ACL's, primarily, as I didn't think CIFS was fine-grained enough to support NTFS permissions and it didn't look like Gluster exports those permission levels, just the base permissions for basic file sharing.

I got the impression that using Gluster would allow for data to be redundant across multiple servers and would speed up access to the files under heavy load, while allowing us to dynamically boost storage capacity by just adding another server and telling Gluster's master node to add that server. Maybe I'm wrong with my understanding of it though. Anyone else use it or care to share how feasible this is?

We have a NAS with relatively slow disks that is choking when users are logging in in the morning. We're migrating user home directories and profiles to a newer, faster server, but I was wondering if it might be wise to look into finding a way to cluster a file server so we can have 2+ servers sharing the access load and network load.

Does DFS do anything like this, or is our best option simply to throw faster hardware at the issue? I'd rather not have to use multiple servers and partition where users are placed so we manually spread the load out, but is that the only real option? How do other people deal with this issue?

The NAS units are running Windows 2003/2008 (the slower one is a dedicated NAS appliance from DELL).

This is a topic that may be rather political but it related to system administration still...how many people do you have supporting your users in your IT department? We have three people supporting something near 1500 systems and around 2400 people and a recent question was raised about why we have long times to get systems replaced, repaired, work orders fulfilled, etc. along with the system admin duties of maintaining the servers (mail, proxy, filters, VOIP, wireless, backup, etc.)

Does anyone have numbers on what the "best practices" average is of support people to employees in an organization?

EDIT:...from some of the answers that are appearing I'm starting to feel depressed...

I'm hoping someone can confirm my observations because I'm questioning my memory...

The title kind of says it all. While working rapidly on deploying a number of similar systems, it appeared that we were able to create systems with the same name and Active Directory allowed us to add them to the domain.

Problem was that one of the machines would no longer "see" the domain, saying it wasn't able to see it anymore.

I removed a machine from the domain and then re-added it with a variation to the name; am I misremembering something, or is it possible to add two machines to AD and effectively drop the other machine from the domain? Am I wrong in thinking this is something that AD shouldn't allow in the first place? I thought it would give a warning, as AD does when you try adding a username that already exists withing the AD structure.

VMWare's vSphere console and Veeam's monitoring utilities do an admirable job of showing admins various statistics on CPU usage, memory usage, percent utilization, etc. of VM's and the hypervisor host.

Is there a similar solution or series of solutions for monitoring a Xen server visually? Monitoring the status of VM's, their resource usage...etc...or is it mainly having to install agents on the virtualized guests and centralize it that way?

We use to have a filtering/proxy setup that was configured so that about 500 users were routed through a Unix-based system running SQUID with SquidGuard to block questionable content and log what users were doing. What we found was that there were some people able to bypass the block by going to free online proxies that use the HTTPS protocol. I couldn't find a way to block HTTPS traffic without disabling it altogether, which wasn't going to work for purchasing and HR (or regular users with banking sites).

Is there a way to block or filter HTTPS traffic with SQUID/Squidguard? Or some other open source monitoring programs? How do others deal with it without resorting to commercial appliances?

EDIT: We're not trying to watch the traffic. We're trying to monitor the urls and block them as necessary. We don't want credit card numbers and such...we wanted to know when Johnny was accessing https://schoolssucksoweproxyforyou.com/playboy.com, add the domain to a blockfile, and prevent them from doing it again. See some added comments below...

EDIT2: (Re: speaking of HR, banking, etc...) You may not think about it that way, but we have a person that does purchasing, our district covers 7 buildings scattered around the county so we have someone in charge of distributing materials and inventory, we have the same people working with checking and banking records, we have people in charge of unions for staff and another for faculty, we have people in charge of dealing with HR information like insurance and injury claims and liability...there's a lot of things involved in running schools that I don't think the general public ever thinks about. Plus we do have issues where it was considered overbearing to prevent staff/faculty from doing online banking, or even students from being able to access certain sites for online use (such as web quests) that sometimes required SSL connections to work, so banning HTTPS outright at the router would not be feasible.

Anyway, moving on to your suggestion about blocking only certain people, I didn't see a way to integrate the functionality in for authentication on a per-user basis; if credentials could be passed along by Windows so users didn't need to keep authenticating with yet another password it would be a workable solution but anything I found was kludgey and didn't work reliably. Then it's an issue of getting people to remember yet another password (or students/staff stealing/sharing passwords). I personally liked having filtering done fairly across the board for staff and students rather than making it an issue of teachers can do X while students aren't considered enough of a person to do that same thing.

In the end I couldn't find a way to get the server to reliably authenticate against Active Directory (to centralize user management and reduce their passwords to remember), or if I used a different authentication scheme it would mean another database to keep in sync with...what, last count, ~1200 users or so? with a high churn as every year we have kids in and out of district, graduating, and new ones coming in?...

I have (as some are probably tired of seeing on SF) a Dell 2950, dual 4 core 3Ghz processors running ESXi. I noticed on the VSphere management console that the server says it doesn't have hyperthreading enabled ("inactive")

Apparently it is by default turned off in the BIOS.

I know I could shut down all the VM's and reboot and edit that setting, but should I? Is there a real benefit to having hyperthreading enabled on this type of setup, or is the performance gain marginal, if any??

Can anyone share their experiences (for example, this was great! This failed miserably!) with using the Hyper-V, ESXi, and XenServer virtualization platforms? Cost? Management? features? Handling load and backups and recovery?

And also minimum server requirements?

I thought Xen was a free virtualization platform for Linux. Is there a Xen and a separate XenServer platform?

Opinions and observations would be appreciated for a test rollout for our organization.

I've used several different tools for repairing disks and have been wondering if there is a list of what exactly CHKDSK can repair? The MFT? Boot sector? Backup boot sector? Clusters? What common issues can't it fix?