CloudMac – OS X Server DNS TTL Modification

Posted by CloudMac.net

For some reasons, you may want to modify the TTL (Time to Live) of a DNS Server.

The default TTL is 10800 seconds (3 hours).  To modify the TTL, edit the following file on your OS X DNS Server and replace $TTL 10800 with the $TTL value you desire.  Please note using a TTL value of 0 (zero) is not supported by some systems and is not advised.

The DNS cache on the client systems may need to be flushed to honor the new TTL.  This is done on OS X by using the “dscacheutil -flush” command.

vi /var/named/zones/db.cloudmac.net.zone.apple

Here is an example config file:

dns1:~ root# cat /var/named/zones/db.cloudmac.net.zone.apple
 ;GUID=D521C96D-AA85-4438-A1BC-8B1D7987DCD0
 ;selfResolvingHostname=0

$TTL 300
cloudmac.net. IN SOA dns.cloudmac.net. netopps.cloudmac.net. (
     2011112804    ;Serial
     86400         ;Refresh
     3600          ;Retry
     604800        ;Expire
     345600        ;Negative caching TTL
 ) 

cloudmac.net. IN  NS dns.cloudmac.net.
dns1 IN  A 10.22.100.30
mail IN  A 10.22.100.31
cloudmac.net. IN  MX 0 mail.cloudmac.net.
dns1:~ root#

Run the dig command to confirm the TTL information reflects what you entered:

dns1:~ root# dig mail.cloudmac.net @10.22.100.30

; <<>> DiG 9.6-ESV-R4-P3 <<>> mail.cloudmac.net @10.22.100.30
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 983
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 1, ADDITIONAL: 1

;; QUESTION SECTION:
;mail.cloudmac.net.        IN    A

;; ANSWER SECTION:
mail.cloudmac.net.    300    IN    A    10.22.100.31

;; AUTHORITY SECTION:
cloudmac.net.        300    IN    NS    dns1.cloudmac.net.

;; ADDITIONAL SECTION:
dns1.cloudmac.net.    300    IN    A    10.22.100.30

;; Query time: 1 msec
;; SERVER: 10.22.100.30#53(10.22.100.30)
;; WHEN: Mon Nov 28 16:47:32 2011
;; MSG SIZE  rcvd: 85

dns1:~ root#

More info is available by following the links below:

Time to live (TTL) – Wikipedia.com

DNS Round Robin – Wikipedia.com

dscacheutil – developer.apple.com

Hitachi Data Systems Announces Acquisition of BlueArc

Hitachi Data Systems Corporation (HDS), a wholly owned subsidiary of Hitachi, Ltd. (NYSE: HIT / TSE: 6501), today announced a significant milestone in its strategy to give customers seamless access to all data, content and information with the acquisition of BlueArc Corporation, a leader in scalable, high performance network storage. Building upon a successful 5 year OEM partnership, Hitachi Data Systems and BlueArc will give customers the unmatched combination of Hitachi enterprise-class quality, reliability and support with innovative, highly scalable, high performance BlueArc network attached storage (NAS).

http://bluearc.com/storage-news/press-releases/110907-Hitachi-Data-Systems-Announces-Acquisition-of-BlueArc.shtml

CloudMac 1000Mbps uplink promotion

Gig-E uplink promo: All customers signing up before May 31st receive a free upgrade with a Gigabit (1000Mbps) uplink port!

Check CloudMac.net for details.

Dedicated Servers!

We are pleased to announce the offering of Dedicated Servers.

Operating Systems Offered:

• OS X Snow Leopard (10.6)

• OS X Snow Leopard Server – Unlimited (10.6)

• CentOS Linux

• RedHat Enterprise Server

• Windows 2008 Server

Hardware Offerings:

• Mac mini
• Mac Pro
• SuperMicro

More information is available on our website:

http://oneiricsys.com/services/dedicated-servers/

Please contact us for pricing inquiries.

OS X Server 10.6.6 Update Released

Apple releases OS X 10.6.6 Server and Client today. Here are are the updates:

This update includes the Mac App Store, a new application you’ll find in the Dock. The Mac App Store includes the following features:

• Discover Mac apps: Browse featured apps, top charts, and categories; or, search for something specific. Read detailed app descriptions and user reviews, and flip through screen shots.

• Buy and install: Easily purchase apps with your iTunes account. Apps install in one step and are quickly available from the Dock.

• App updates: The Mac App Store keeps track of all your purchased apps and notifies you when free updates are available.

Additional improvements

• Fixes a DNS resolution issue for Mac OS X Server v10.6.5. The system now properly resolves a DNS alias (CNAME) that points to a host in a .local domain.

• Improves Mac OS X Server security. For more information about the security content of Mac OS X Server v10.6.5 see this article.

• Includes all the improvements in the previous 10.6.1, 10.6.2, 10.6.3, 10.6.4 and 10.6.5 updates.

• Mac OS X Server v10.6.6 also includes all improvements delivered in the client Mac OS X v10.6.6 Update.

More information is available on Apple’s site: http://support.apple.com/kb/HT4460

CloudMac Dedicated Mac mini July special

CloudMac is offering a special on Dedicated Mac mini’s running OS X 10.6 Server.  The promo includes 100Mbps Internet connectivity, 250GB monthly and all the other offerings standard with the Dedicate Server plan.

As always, all hosting options are month-to-month with $0 setup fee.  For more info, please visit http://cloudmac.net/l/july_special

Offer available while servers are available.

Apple Server Hosting

CloudMac (http://cloudmac.net/), an Oneiric Systems Company, is focused on providing hosting and server colocation for OS X Servers.

For more information, please refer to the site and CloudMac blog.

How to reset ifconfig counters

Sometimes it is nice to reset the counters ifconfig displays.  This could be done monthly to show detailed bandwidth transfers each month, or after a specific event.  To do so, execute the following commands:

Deleting specific history from Firefox

To delete specific URL’s from Firefox, simple click on them and hit shift+delete.  This is nice if the URL does not exist, or if it was entered in error.

Thinklogical KVM

We are testing the Thinklogical KVM for a large POC.  The solution allows for dual DVI, USB 2, Serial and PS2 support.  The device worked out of the box, and supported our Dell monitors running 1680×1050.  The audio quality is also great, which is a setback on other IP based KVM solutions.

Overall, we are very impressed with the Thinklogical unit.