Re: [CentOS] xm console -- what should I get?

[Yordan Georgiev]

xm console ID
[enter]
[enter]

On Thu, Jul 15, 2010 at 10:00 PM, David Dyer-Bennet  wrote:
> If I type "xm console 6", say (when I have a virtual machine 6 running),
> what should I get?
>
> The documentation seems to indicate that I should get something that
> behaves like a telnet to a serial console.
>
> What I actually get is a connection that might show me a couple of lines
> of output that do look like they belonged on the console, but doesn't seem
> to accept any input (except that it does exit on the documented escape
> character ^[).
>
> These virtual systems show as running, and in fact with virt-viewer I can
> get a VNC console to them.
>
> Dom0 and the guests are Centos 5.5 x64, running on Intel processors with
> modern virtualization support (turned on in the bios, and it looks like
> Xen found it from xm dmesg output).
>
> --
> David Dyer-Bennet, d...@dd-b.net; http://dd-b.net/
> Snapshots: http://dd-b.net/dd-b/SnapshotAlbum/data/
> Photos: http://dd-b.net/photography/gallery/
> Dragaera: http://dragaera.info
>
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Re: [CentOS] xm console -- what should I get?

[Kwan Lowe]

On Thu, Jul 15, 2010 at 3:00 PM, David Dyer-Bennet  wrote:
> If I type "xm console 6", say (when I have a virtual machine 6 running),
> what should I get?
>
> The documentation seems to indicate that I should get something that
> behaves like a telnet to a serial console.
>
> What I actually get is a connection that might show me a couple of lines
> of output that do look like they belonged on the console, but doesn't seem
> to accept any input (except that it does exit on the documented escape
> character ^[).
>
> These virtual systems show as running, and in fact with virt-viewer I can
> get a VNC console to them.

I had a similar problem and had to add the following to the
/etc/inittab in the guest systems to get it working:

# Run gettys in standard runlevels
co:2345:respawn:/sbin/agetty xvc0 9600 vt100-nav

Reload the inittab once changed then try attaching via the xm again.
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Re: [CentOS] xm console -- what should I get?

[Theo Band]

David Dyer-Bennet wrote:
> If I type "xm console 6", say (when I have a virtual machine 6 running),
> what should I get?
>
> The documentation seems to indicate that I should get something that
> behaves like a telnet to a serial console.
>
> What I actually get is a connection that might show me a couple of lines
> of output that do look like they belonged on the console, but doesn't seem
> to accept any input (except that it does exit on the documented escape
> character ^[).
>
> These virtual systems show as running, and in fact with virt-viewer I can
> get a VNC console to them.
>
> Dom0 and the guests are Centos 5.5 x64, running on Intel processors with
> modern virtualization support (turned on in the bios, and it looks like
> Xen found it from xm dmesg output).
>   
It works for para-virtualized guests (with xen kernel) not for
fully-virtualized ones.

Theo
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[CentOS] Subject=Re:CentOS Simple solution for small network in school

[Paul Schoonderwoerd]

Hello,

I would use some (old) pc's as thin clients and have them boot over the 
network from the server, or from cd. Then, have them make a connection to the 
server with the NX protocol. Thinstation.org provides all this.
Just install FreeNX on the server (yum install) and manage the accounts as 
local accounts.
Can't have it any simpeler than that in my opinion, also for management.

Regards,
-- 
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Pollux IT - Open Source oplossingen & Netwerk beveiliging
http://www.Pollux-IT.nl
0294-283832
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Re: [CentOS] Finding DHCP IP of guest system

[David Dyer-Bennet]

On Fri, July 16, 2010 01:56, Rudi Ahlers wrote:
> On Thu, Jul 15, 2010 at 10:06 PM, David Dyer-Bennet  wrote:
>>
>> My dom0 /var/log/messages doesn't have anything on assignments to
>> guests.
>> bs004 (ID 9), for example, currently has 192.168.1.143, but there's
>> nothing about that IP in dom0 /var/log/messages.
>>
>> Are you maybe running a dhcp server locally for local networking, rather
>> than bridging your guest systems out to the general dhcp server?
>
> I don't run DHCP on dom0 (are you using XEN?)  for this very reason. I
> don't want DHCP broadcasts all over the network, and don't want the
> domU's to accept DHCP requests from other hosts.

Yes, Xen.  I'm not so far as I know running DHCP, but it might be
configured by default.

> DHCP *normally* logs to /var/log/messages, unless you configured it
> otherwise.

Haven't touched anything of that nature (and the install is only hours
old, I still remember what I did :-) ).

> try "grep dhcp /var/log/messages"
>
> OR "tail -f /var/log/messages" and then "service network restart" on a
> domU to see if it shows anything on dom0. Can the domU's get their IP
> from another server? Try en eliminate this altogether.

The domU got it's ip from the corporate DHCP server, which is what I
intended (that's why I'm running bridged, I'm using virtual servers to
separate functions while conserving physical boxes, so I want them to
present as separate systems to users on the network).

Can't retest right now, as I'm back to just a newly installed Dom0 for
what I hope will be the actual production install.

-- 
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Snapshots: http://dd-b.net/dd-b/SnapshotAlbum/data/
Photos: http://dd-b.net/photography/gallery/
Dragaera: http://dragaera.info

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Re: [CentOS] Finding DHCP IP of guest system

[Akemi Yagi]

On Thu, Jul 15, 2010 at 12:03 PM, David Dyer-Bennet  wrote:
> If I can log in to the guest through the console, I can of course find out
> what IP DHCP has assigned it.  If I configure a static IP I can of course
> connect to the system there (if it runs services, the firewall allows it,
> all the usual caveats).
>
> Does there happen to be any way to determine from dom0 what IPs are
> participating in the network and which guests they belong to?  (I'm
> configuring everything as bridged; basically I want to use virtualization
> to pretend I have a bunch of independent systems visible to the outside.)

Soon after I started using kvm and created guests with bridged
network, I asked the same question as yours. I have not been able to
find a clear answer to date.  If I'm not mistaken, there is no easy
solution as you suspected. The host has no knowledge of the guests'
IPs because an outside DHCP server (in my case at home, it is a
router/cable modem) provides the IP addresses. So, I've been using the
"console" method.

Akemi
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Re: [CentOS] xm console -- what should I get?

[Gordon Messmer]

On 07/16/2010 05:06 AM, Theo Band wrote:
> It works for para-virtualized guests (with xen kernel) not for
> fully-virtualized ones.

For fully-virtualized guests, make sure the guest definition contains:

   
 
   
   
 
   

If you add this, you'll need to redefine the guest, then shut it down 
completely ("poweroff" the guest, not reboot).

# virsh define /etc/libvirt/qemu/guest.xml

Once a serial console is defined in the guest, set up grub.  Edit 
/boot/grub/grub.conf and replace the timeout, splashimage, and 
hiddenmenu lines with:

timeout=5
serial --unit=0 --speed=115200 --word=8 --parity=no --stop=1
terminal --timeout=5 serial console

Make sure all of the "kernel" lines contain a serial console arg:

 kernel /boot/vmlinuz-... ro root=LABEL=/ console=ttyS0,115200

And finally make sure that /etc/inittab starts a getty on the serial 
console:

s0:2345:respawn:/sbin/agetty -L 115200 ttyS0 vt100

The last three are the same steps you'd take to set up a machine with a 
physical serial console.
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Re: [CentOS] Finding DHCP IP of guest system

[Les Mikesell]

On 7/16/2010 10:11 AM, Akemi Yagi wrote:
> On Thu, Jul 15, 2010 at 12:03 PM, David Dyer-Bennet  wrote:
>> If I can log in to the guest through the console, I can of course find out
>> what IP DHCP has assigned it.  If I configure a static IP I can of course
>> connect to the system there (if it runs services, the firewall allows it,
>> all the usual caveats).
>>
>> Does there happen to be any way to determine from dom0 what IPs are
>> participating in the network and which guests they belong to?  (I'm
>> configuring everything as bridged; basically I want to use virtualization
>> to pretend I have a bunch of independent systems visible to the outside.)
>
> Soon after I started using kvm and created guests with bridged
> network, I asked the same question as yours. I have not been able to
> find a clear answer to date.  If I'm not mistaken, there is no easy
> solution as you suspected. The host has no knowledge of the guests'
> IPs because an outside DHCP server (in my case at home, it is a
> router/cable modem) provides the IP addresses. So, I've been using the
> "console" method.

Your router/cablemodem most likely has a web interface where you can 
find a log and a mapping of MAC addresses to the IP addresses it has 
given out.  You might even be able to configure it to syslog to your 
centos box.  You should also be able to see the DHCP traffic activity by 
running tcpdump or wireshark on the bridged host physical interface as 
the guest starts.

-- 
   Les Mikesell
lesmikes...@gmail.com

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Re: [CentOS] Finding DHCP IP of guest system

[Akemi Yagi]

On Fri, Jul 16, 2010 at 8:40 AM, Les Mikesell  wrote:
> On 7/16/2010 10:11 AM, Akemi Yagi wrote:

>> Soon after I started using kvm and created guests with bridged
>> network, I asked the same question as yours. I have not been able to
>> find a clear answer to date.  If I'm not mistaken, there is no easy
>> solution as you suspected. The host has no knowledge of the guests'
>> IPs because an outside DHCP server (in my case at home, it is a
>> router/cable modem) provides the IP addresses. So, I've been using the
>> "console" method.
>
> Your router/cablemodem most likely has a web interface where you can
> find a log and a mapping of MAC addresses to the IP addresses it has
> given out.  You might even be able to configure it to syslog to your
> centos box.  You should also be able to see the DHCP traffic activity by
> running tcpdump or wireshark on the bridged host physical interface as
> the guest starts.

Sure, I can retrieve the info from my cable modem. I also tried
wireshark. I then decided looking at the console was much "quicker"
for me. But if I'm in a situation where the guests are constantly
created and there is a need for semi-automatic retrieval of guest's
IPs, I would spend some time for that.

Akemi
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Re: [CentOS] Finding DHCP IP of guest system

[Karanbir Singh]

On 07/16/2010 04:57 PM, Akemi Yagi wrote:
> Sure, I can retrieve the info from my cable modem. I also tried
> wireshark. I then decided looking at the console was much "quicker"
> for me. But if I'm in a situation where the guests are constantly
> created and there is a need for semi-automatic retrieval of guest's
> IPs, I would spend some time for that.

This isnt hard at all, just setup your dhcp server to update dns and 
parse the bind dbdumps whenever you care to find out whats live at this 
time.

- KB
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[CentOS] Error message downloading latest Spamassassin data files via sa-update

[Gilbert Sebenste]

Hello everyone,

When I type "sa-update" to get the latest files for Spamassassin, I see 
this error:

]# sa-update
Argument "1.39_01" isn't numeric in subroutine entry at /usr/bin/sa-update 
line 83.

My Google-fu came up with nothing when searching for this error. Am I the 
only one getting this to happen, or are any of you seeing it as well?

Gilbert

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(My opinions only!)  **
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Re: [CentOS] Error message downloading latest Spamassassin data files via sa-update

[Frank Cox]

On Fri, 2010-07-16 at 11:44 -0500, Gilbert Sebenste wrote:
> My Google-fu came up with nothing when searching for this error. Am I the 
> only one getting this to happen, or are any of you seeing it as well?

http://bugs.centos.org/view.php?id=4438

-- 
MELVILLE THEATRE ~ Melville Sask ~ http://www.melvilletheatre.com

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Re: [CentOS] Error message downloading latest Spamassassin data files via sa-update

[Akemi Yagi]

On Fri, Jul 16, 2010 at 9:44 AM, Gilbert Sebenste
 wrote:
> Hello everyone,
>
> When I type "sa-update" to get the latest files for Spamassassin, I see
> this error:
>
> ]# sa-update
> Argument "1.39_01" isn't numeric in subroutine entry at /usr/bin/sa-update
> line 83.
>
> My Google-fu came up with nothing when searching for this error. Am I the
> only one getting this to happen, or are any of you seeing it as well?

It is a known issue.  Please see:

https://bugzilla.redhat.com/show_bug.cgi?id=612879
http://bugs.centos.org/view.php?id=4438

to find a workaround.

Akemi
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[CentOS] Xen / KVM CentOS-5 How To Document

[gene . poole]

Does anyone have any idea where I can locate a 'GOOD' how-to document on 
implementing Xen and/or KVM on a CentOS-5.3 system?  I'm currently running 
VMware Server 2.0.2, but I would like to make the move to the open source 
virtualization - if possible.  What I found is somewhat short on the 
networking piece.  It doesn't matter if it's TUI or GUI.

Thanks,
Gene Poole
gene.po...@macys.com
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Re: [CentOS] Xen / KVM CentOS-5 How To Document

[Christopher Mills]

I use the article on the centos wiki for Xen.

On 7/16/10, gene.po...@macys.com  wrote:
> Does anyone have any idea where I can locate a 'GOOD' how-to document on
> implementing Xen and/or KVM on a CentOS-5.3 system?  I'm currently running
> VMware Server 2.0.2, but I would like to make the move to the open source
> virtualization - if possible.  What I found is somewhat short on the
> networking piece.  It doesn't matter if it's TUI or GUI.
>
> Thanks,
> Gene Poole
> gene.po...@macys.com
>
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[CentOS] Desktop Supercomputer

[Rajagopal Swaminathan]

Greetings,

Have been looking at the specs of Boston Venom T4000.

Boston Venom T4000
http://www.bostonindia.in/products/bos-t4000.aspx

I could not figure out the lowest base price points, HA features and KVM support

Yet to work out the storage part of say 8TB storage (with HA features,
of course) for this beast.

and accessability issues from devices.

I am in the middle of trying to find out about What AMD has been doing
in its end.

and Lastly, wireless fencing devices

Yet to look into easy monitoring and management tools.

Any opinions please?

Regards,

Rajagopal
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Re: [CentOS] Error message downloading latest Spamassassin data files via sa-update

[Gilbert Sebenste]

Thanks, everyone. I'll wait for an updated package. From what I see, and 
with high-end paid users yelling about it, a fix should be in short order.

***
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(My opinions only!)  **
Staff Meteorologist, Northern Illinois University  
E-mail: seben...@weather.admin.niu.edu  ***
web: http://weather.admin.niu.edu  **
***
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Re: [CentOS] Desktop Supercomputer

[John R Pierce]

On 07/16/10 11:01 AM, Rajagopal Swaminathan wrote:

Greetings,

Have been looking at the specs of Boston Venom T4000.

Boston Venom T4000
http://www.bostonindia.in/products/bos-t4000.aspx

I could not figure out the lowest base price points, HA features and KVM support
   


is your goal a "server" or "supercomputing"?  all that tesla stuff sorta 
says supercomputing, while HA etc says 'server'.


supercomputer clusters eschew HA in favor of having many independent 
compute units in a loose cluster that can tolerate any node dying by 
simply reassigning its last work unit to another node.  only the 
persistent storage (usually a SAN or a clustered file system), and the 
cluster controller needs conventional HA.



if your goal is a 'server', then something from here would likely be 
more suitable.

http://h10010.www1.hp.com/wwpc/us/en/sm/WF04a/15351-15351-3328412-241644-241475.html
http://www-03.ibm.com/systems/x/hardware/rack/index.html
http://www.dell.com/us/en/business/servers/rack_optimized/ct.aspx?refid=rack_optimized&s=bsd&cs=04 


http://www.supermicro.com/products/system/2U/

along with the appropriate storage etc, depending on your requirements.


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Re: [CentOS] Xen / KVM CentOS-5 How To Document

[Markus Falb]

-BEGIN PGP SIGNED MESSAGE-
Hash: SHA1

On 16/07/2010 19:47, gene.po...@macys.com
wrote:
> Does anyone have any idea where I can locate a 'GOOD' how-to document on
> implementing Xen and/or KVM on a CentOS-5.3 system?  I'm currently
> running VMware Server 2.0.2, but I would like to make the move to the
> open source virtualization - if possible.  What I found is somewhat
> short on the networking piece.  It doesn't matter if it's TUI or GUI.

The Upstream Vendors Virtualization Guide comes to me mind, to be found
on following link.

http://www.redhat.com/docs/manuals/enterprise/

- -- 
Regards, Markus
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Re: [CentOS] Xen / KVM CentOS-5 How To Document

[Mike Hanby]

This is the full upstream manual, not really a how to, but a good reference to 
keep bookmarked:
http://www.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/5.5/html/Virtualization_Guide/index.html

As for a how to, this ones pretty basic but might be enough to answer your 
questions:
http://www.banym.de/projects/centos-fedora/install-kvm-on-centos-5.4

Mike

-Original Message-
From: centos-boun...@centos.org [mailto:centos-boun...@centos.org] On Behalf Of 
Markus Falb
Sent: Friday, July 16, 2010 2:57 PM
To: centos@centos.org
Subject: Re: [CentOS] Xen / KVM CentOS-5 How To Document

-BEGIN PGP SIGNED MESSAGE-
Hash: SHA1

On 16/07/2010 19:47, gene.po...@macys.com
wrote:
> Does anyone have any idea where I can locate a 'GOOD' how-to document on
> implementing Xen and/or KVM on a CentOS-5.3 system?  I'm currently
> running VMware Server 2.0.2, but I would like to make the move to the
> open source virtualization - if possible.  What I found is somewhat
> short on the networking piece.  It doesn't matter if it's TUI or GUI.

The Upstream Vendors Virtualization Guide comes to me mind, to be found
on following link.

http://www.redhat.com/docs/manuals/enterprise/

- -- 
Regards, Markus
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[CentOS] noReplaceConfig equivalent for /etc/yum.conf

[FHDATA]

Greetings,


In up2date config file there is a directive by the name of 
noReplaceConfig . . .

Do you know what is the /etc/yum.conf equivalent for that?

noReplaceConfig[comment]=When selected, no packages that would change
configuration data are automatically installed
noReplaceConfig=1


Thank you,

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Re: [CentOS] Desktop Supercomputer

[Karanbir Singh]

On 07/16/2010 07:01 PM, Rajagopal Swaminathan wrote:
> Greetings,
>
> Have been looking at the specs of Boston Venom T4000.
>
Couple of things :
- dont crosspost, its considered rude
- Find a relevant place to post your querries

- KB
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Re: [CentOS] noReplaceConfig equivalent for /etc/yum.conf

[Karanbir Singh]

On 07/16/2010 11:44 PM, FHDATA wrote:
> noReplaceConfig[comment]=When selected, no packages that would change
> configuration data are automatically installed
> noReplaceConfig=1


yum does not automatically install anything. you would need to initiate 
an install / update operation by hand.

Having said that, it should not be too hard to write a plugin that would 
force a user confirm for any package that drops or touches a file in 
/etc ( assuming you can get to a stage where /etc/* does represent all 
config data on a machine ).

Alternatively, you could do it where the package payload is checked for 
config metadata.

- KB
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Re: [CentOS] Finding DHCP IP of guest system

[Kahlil Hodgson]

On 07/17/2010 12:39 AM, David Dyer-Bennet wrote:
> The domU got it's ip from the corporate DHCP server, which is what I
> intended (that's why I'm running bridged, I'm using virtual servers to
> separate functions while conserving physical boxes, so I want them to
> present as separate systems to users on the network).

An alternative, if you have some control over the DHCP server, might be
to enforce a mapping of MAC addresses to IPs.  You can pretty much set
you guest MAC addresses to whatever you want so long as they don't
conflict with anything else. In libvirt land you do that with something like

 
  
  


Kal
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Re: [CentOS] Finding DHCP IP of guest system

[Jay Leafey]

I had the same issue on my local network (DHCP server could not update 
DNS) so I cobbled up a shell script that runs periodically to update DNS 
manually.  It does a ping-sweep using "nmap -sP 192.168.1.0/24" and 
parses the output.  The output (obfuscated and abbreviated) looks like this:



Starting Nmap 4.11 ( http://www.insecure.org/nmap/ ) at 2010-07-16 20:53 CDT
Host 192.168.1.1 appears to be up.
MAC Address: **:**:**:**:**:** (Unknown)
Host 192.168.1.2 appears to be up.
MAC Address: **:**:**:**:**:** (Compaq Computer)
Host workstation.local (192.168.1.5) appears to be up.
MAC Address: **:**:**:**:**:** (Hewlett Packard)
Host printer.local (192.168.1.9) appears to be up.


In my case, I added the MAC address/DNS name pairs in /etc/ethers and 
use that to drive the process.  I've even got a few VMware hosts with 
bridged interfaces, they work the same as the physical machines.


Admittedly, it's a heck of a kludge.
--
Jay Leafey - jay.lea...@mindless.com
Memphis, TN


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Re: [CentOS] Desktop Supercomputer

[Rajagopal Swaminathan]

Greetings,

On 7/17/10, John R Pierce  wrote:
> On 07/16/10 11:01 AM, Rajagopal Swaminathan wrote:
>
> is your goal a "server" or "supercomputing"?  all that tesla stuff sorta
> says supercomputing, while HA etc says 'server'.
>
> supercomputer clusters eschew HA in favor of having many independent
> compute units in a loose cluster that can tolerate any node dying by
> simply reassigning its last work unit to another node.  only the
> persistent storage (usually a SAN or a clustered file system), and the
> cluster controller needs conventional HA.
>

I was thinking more about a "personal supercomputer in a cloud"

HA is a requirement for cloud. So I guess I have to think further about it.

ideas welcome.

Regards,

Rajagopal
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Re: [CentOS] Finding DHCP IP of guest system

[JohnS]

On Fri, 2010-07-16 at 20:59 -0500, Jay Leafey wrote:
> I had the same issue on my local network (DHCP server could not update 
> DNS) so I cobbled up a shell script that runs periodically to update DNS 
> manually.  It does a ping-sweep using "nmap -sP 192.168.1.0/24" and 
> parses the output.  The output (obfuscated and abbreviated) looks like this:
> 
> > Starting Nmap 4.11 ( http://www.insecure.org/nmap/ ) at 2010-07-16 20:53 CDT
> > Host 192.168.1.1 appears to be up.
> > MAC Address: **:**:**:**:**:** (Unknown)
> > Host 192.168.1.2 appears to be up.
> > MAC Address: **:**:**:**:**:** (Compaq Computer)
> > Host workstation.local (192.168.1.5) appears to be up.
> > MAC Address: **:**:**:**:**:** (Hewlett Packard)
> > Host printer.local (192.168.1.9) appears to be up.
> 
> In my case, I added the MAC address/DNS name pairs in /etc/ethers and 
> use that to drive the process.  I've even got a few VMware hosts with 
> bridged interfaces, they work the same as the physical machines.
> 
> Admittedly, it's a heck of a kludge.
---
Awsome but a Day Late and a Dollar Short && Care to share that shell
script please.
&& Why you scrub the MACS?

John 

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Re: [CentOS] Finding DHCP IP of guest system

[Jay Leafey]

JohnS wrote:

Awsome but a Day Late and a Dollar Short && Care to share that shell
script please.


OK, but I warned you, it's a kludge.


#!/bin/bash
#
#  Get a list of the hosts on the local network via nmap -sP and check 
#  them against the ethers file to retrieve the host name, if any.  
#  Check DNS to see if the DNS entries match it in the local domain and, 
#  if not, make the necessary changes.

#
#  $Id$
#  Jay Leafey - 10/29/2009
#

TEST=0
test $# -gt 0 && TEST=1

NSUPDATES=$( mktemp -t dynamic_dns.XX )
ME=$( hostname -f )

echo "server localhost" > ${NSUPDATES}

nmap -sP 192.168.1.0/24 | \
while read f1 f2 f3 f4 f5
do
if [ "${f1}" == "Host" ]
then
if [ "${f2}" == "${ME}" ]
then
continue
fi
read m1 m2 m3 m4 m5
MYIP=""
if [ "${f2%.*}" == "192.168.1" ]
then
MYIP=${f2}
else
MYIP=$( echo "${f3}" | sed 's/[\(\)]//g' )
fi
MYMAC=${m3}
MYHOST=$( grep -i "^${MYMAC}" /etc/ethers | awk "{ print \$2 }" 
| tr A-Z a-z)
#~ echo "${MYMAC} ${MYIP} ${MYHOST}"

if [ "${MYHOST}" ]
then
#~ Set the "forward" DNS entry
DNSIP=$( host ${MYHOST} 2>/dev/null | awk '/ has 
address / { print $NF}' )
if [ -z "${DNSIP}" ]
then
echo -e "update add ${MYHOST}.local 2400 IN A 
${MYIP}\n" >> ${NSUPDATES}
elif [ "${MYIP}" != "${DNSIP}" ]
then
echo "update delete ${MYHOST}.local IN A ${DNSIP}" 
>> ${NSUPDATES}
echo -e "update add ${MYHOST}.local 240 IN A 
${MYIP}\n" >> ${NSUPDATES}
fi
#~ Set the "reverse" DNS entry
DNSRR=$( host ${MYIP} | awk '/ domain name pointer / { 
print $1 }' )
DNSPTR=$( host ${MYIP} | awk '/ domain name pointer / { 
print $NF }' )
if [ -z "${DNSPTR}" ]
then
echo -e "update add ${MYIP##*.}.1.168.192.in-addr.arpa 
2400 IN PTR ${MYHOST}.local.\n" >> ${NSUPDATES}
elif [ "${DNSPTR}" != "${MYHOST}.local." ]
then
echo "update delete ${DNSRR} IN PTR" >> 
${NSUPDATES}
echo -e "update add ${DNSRR} 2400 IN PTR 
${MYHOST}.local.\n" >> ${NSUPDATES}
fi
fi
fi
done 


if [ ${TEST} -gt 0 ]
then
cat ${NSUPDATES}
exit
fi

if [ $( wc -l ${NSUPDATES} ) -gt 1 ]
then
#cat ${NSUPDATES}
nsupdate ${NSUPDATES}
if [ $? -ne 0 ]
then
echo "nsupdate failed:"
cat ${NSUPDATES}
fi
fi

rm -f ${NSUPDATES}

exit


The code makes a LOT of assumptions that may only be valid in my home 
network, but perhaps the ideas will be useful.  I have considered 
rewriting this in Perl, but it works and I really need the time for 
other projects.



&& Why you scrub the MACS?


Sheer paranoia and long-standing habit.

Enjoy!
--
Jay Leafey - jay.lea...@mindless.com
Memphis, TN


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Re: [CentOS] Desktop Supercomputer

[John R Pierce]

On 07/16/10 7:12 PM, Rajagopal Swaminathan wrote:
> HA is a requirement for cloud.

it is?

Most clouds have their own integral resilience that negates the need for 
conventional HA techniques.



but, really, "Cloud" is about the most meaningless buzzword in current 
usage.  it can mean anything from renting Amazon E2 server instances, 
to  deploying distributed applications on google's BigTable 
infrastructure to moving your older physical servers to vmware esx farms.


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Re: [CentOS] Finding DHCP IP of guest system

[JohnS]

On Sat, 2010-07-17 at 00:21 -0500, Jay Leafey wrote:
> JohnS wrote:
> > Awsome but a Day Late and a Dollar Short && Care to share that shell
> > script please.
> 
> OK, but I warned you, it's a kludge.

Well it's a lil better then nothing at all right?

> The code makes a LOT of assumptions that may only be valid in my home 
> network, but perhaps the ideas will be useful.  I have considered 
> rewriting this in Perl, but it works and I really need the time for 
> other projects.

It's the ideas that I like to see and the methodology behind it.  I have
to admit I liked the idea of the /etc/eth file for MAC to Hostname
translation.

> > && Why you scrub the MACS?
> 
> Sheer paranoia and long-standing habit.

Elaborate, you that paranoid?  Over paranoid gets you faster than
scrubing MACs.  I would worry about, does my router have holes in it?
Plus let your MAC fly on the wireless network.  I let my neighbor
connect to mine, they can't afford the internet.  One caveat, all they
have is net access.

John

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