Tag: technology

Synology for FreeBSD backups

How I configured a Synology NAS as a backup server, using NFS and AMD on FreeBSD.

In February 2013, a client purchased a Synology NAS. They hired me to set up their mail server to back up to it each night. In addition, I wrote them a restore script. After an email address is specified, it presents a list of available snapshots and provides the ability to restore mailbox contents. It is now September, the solution has been working flawlessly, so I’m sharing a few details.

To fully preserve the permissions, ownership, and metadata, mounting the Synology via NFS was the best option. A potential issue with NFS is that the mail server would be hung if the Synology was unavailable. Because the NAS is only used for backups, I chose to automount the NFS share. That reduces the window for NFS hang exposure to about 20 minutes a day.

To configure automounter, I added this entry to /etc/fstab:

10.10.10.10:/volume1/mail /mnt/synology nfs rw,noauto 0 0

and these entries to /etc/rc.conf:

amd_enable=”YES”
amd_flags=”-a /.amd_mnt -l syslog /mnt/synology /etc/amd.synology”

and this to /etc/amd.synology:

/defaults type:=nfs;opts:=rw,grpid,resvport,vers=3,proto=tcp
* rhost:=synology;rfs:=/volume1/mail/snapshots

Once the automounter (amd) was properly configured, it was a simple matter to install and configure rsnapshot. Each night, the periodic scripts triggers the backup which automounts the NAS. Shortly after the backups conclude, amd disconnects it.

AT&T cramming: Part 2

In 2011, a miscreant abused AT&T’s Wireless Access Protocol payment system and add unauthorized charges to my account. When I noticed the charges, I called AT&T. After getting the initial “we can only refund 3 months” runaround, I escalated the matter  until I got a full refund. I also had AT&T add Purchase Blocker to all 4 of my lines.

Today I logged in to my AT&T account and noticed that, quite helpfully, AT&T now highlights these “billed mobile purchases.” Unfortunately, two new recurring charges were added to my account in January. Jesta, one of the companies behind the crammed charges are self-professed scammers that were fined $1.2M by the FTC in August. As part of the judgement, they are required to refund all charges when customers request it.

AT&T knowingly allows these scammers to bill AT&T customers, which greatly peeves me. I tallied up the charges, called AT&T, and requested a full refund. After getting the same “we can only refund 60 days” runaround, I again escalated the matter and have a full refund being processed. AT&T has no idea why Purchase Blocker got dropped from two of my lines but it has been re-added.

The most interesting part is the email excerpts from Jesta cited in the FTC complaint. Beyond admitting their business is a scam, they discuss ways to keep their return rate below 17%, the rate at which T-Mobile takes away Jesta’s ability to charge customers. AT&T cares even less for their customers and is willing to let scammers reach a 18.5% return rate. Is there any legitimate business with return rates above 10%?

the ROI on LED

Did you do a break even analysis yet? How long will it take you to recoup the expense?

The way to calculate break even (or Return On Investment) is to know roughly how much each bulb costs to use. To determine that, I built a spreadsheet that listed all 49 light fixtures in my house, the number of bulbs in each fixture, watts per bulb, lumens, and the estimated hours of monthly use. From that list, I picked the 24 most expensive bulbs to operate and replaced them with LEDs, at the cost of $217.

Conclusions:

  • Halogen track lights are horrifically inefficient. Replace immediately.
  • Old transformers are terribly inefficient. Replace immediately.
  • LED track light bulbs are hard to find locally and horrifically expensive. Instead, buy direct from China.
  • Considering their lumen output, 4′ fluorescent bulbs aren’t that bad
  • The ROI is usually less than a year for bulbs used more than an hour a day

For the bulbs in my “top 24” list, the ROI period was less than 12 months, and that was purchasing the bulbs at late 2012 prices. Today I can buy most of those bulbs for about 30% less, so the ROI is even faster. Today at Costco, I purchased 850 lumen dimmable LED bulbs for $8 each.

Also consider that many of the bulbs I replaced were CFL. The savings in going from CFL to LED are much lower than when switching from incandescent, lowering my ROI. But the instant on, dimming, and improved light quality of LED bulbs make the switch worth while.

What LED’s do you recommend?

I recommend whatever LED bulbs cost about $10 for 850 or more lumens. I would buy them only at a local store with a good return policy. Out of 40 bulbs, I’ve had two fail. At $10/ea, they cost just enough that it’s worth taking them back for an exchange.

It’s worth noting that both my bulb failures were on the same power circuit as the 12v track lights, and I suspect the 12v power transformer played a role in their failures.

Did you bypass CFL altogether?

We used many CFL bulbs from 2009-2012. The light quality of the earliest ones was quite awful, so we confined them to areas where that didn’t matter. Price was never an issue, as Seattle City Light subsidizes them: a 6-pack of CFL bulbs has cost $1 for years now. As CFL bulb quality improved, CFL bulbs found their way into more rooms. But unlike LED bulbs, they never became good enough that we liked them.

eGallon

The eGallon is a new and more comprehensible way to compare the fuel costs of gas versus electric cars. The eGallon is the cost of driving an electric car the equivalent distance that a gas powered car would travel on 1 gallon of gas.

According to the U.S. Department of Energy, here in the Northwest an eGallon costs $0.84 versus gasoline at $3.87 per gallon. In most states, the cost per eGallon is about 1/3 that of gasoline. If the Chevy Volt and Nissan Leaf didn’t have $10,000 price premiums, one of our cars would be electric.

LED light bulbs

Matt's Household Electric usage
Jun-May Household Electric Use

The graph above from Seattle City Light shows 12 months of our household electric usage (Jun-May). Each bar is 2 months, so the first is Jun-Jul and the last is Apr-May. The lighter colored left bar is the prior years usage, and the darker colored right bar is the current year (Jun 2012-May 2013) usage. Can you guess in which 2-month period I replaced all our light bulbs with LEDs?

Geeky things to do with DMARC

May 25th edition.

Between 2013-05-24 17:00:00 and 2013-05-25 16:59:59, somebody at the United States Army base in Fort Huachuca, Arizona (home of the “U.S. Army Intelligence Center and the U.S. Army Network Enterprise Technology Command (NETCOM)/9th Army Signal Command”) attempted to forge an email to a Yahoo email address purporting to be from my domain cadillac.net.

I discovered this while testing the report analysis tools in Mail::DMARC, my nearly complete implementation of DMARC. DMARC is a nifty bit of tech where mail server operators (in this case, Yahoo!) report message delivery information to domain owners (in this case, me). In this case, Yahoo received the non-conforming message attempt from IP 141.116.211.97, which resolves to host-141-116-211-97.ptr.hqda.pentagon.mil. GeoIP locates the IP at:

US, AZ, Fort Huachuca, 85613, 31.527300, -110.360703, 789, 520.

Because the message didn’t conform to my published DMARC policy, Yahoo rejected it and reported information about the attempt to me. To rule out the possibility of this being a legit message being forwarded, I checked my logs and found zero messages being sent from that domain during the time period. I’d be quite curious to hear an explanation for this attempt.

DKIM and mailing lists

I recently deployed DKIM on a number of my domains. For those readers of my blog that are unfamiliar with DKIM (Hi Mom and Dad, I love you.), DKIM is just a fancy way to stamp emails with a special digital signature. DKIM makes it so other mail programs can inspect the message and determine if it really is from me.

I also manage a number of email lists, and I subscribe to a number of other lists. Email lists have a habit of appending trailers with helpful instructions for managing subscriptions, and adding prefixes to the subject. This altering of the message as it passes through the mailing list invalidates the DKIM signature.

Today I tested a “fix” for one of my Ezmlm mailing lists with these commands:

cd path/to/ezmlm/list; rm prefix  text/trailer addtrailer

Then I sent a test email to the list, and voila, the message passes DKIM validation.

How domain registrations were done in 1996

Received: from ic.net (falcon.ic.net [152.160.101.1]) by ops.internic.net
(8.7.4/InterNIC-RS) with SMTP id CAA03959 for ;
Fri, 12 Apr 1996 02:12:39 -0400 (EDT)
Received: from michweb.net by ic.net with smtp
     (Smail3.1.28.1 #6) id m0u7S0n-003EooC; Thu, 11 Apr 96 15:26 WET DST
Date: Thu, 11 Apr 96 15:26 WET DST
From: matt@michweb.net (Matt Simerson)
To: HOSTMASTER@INTERNIC.NET
Subject: [NIC-960412.367] NEW DOMAIN
Message-ID:
MIME-Version: 1.0
Received: from porthos.michweb.net [152.160.182.5] by michweb.net
  with ESMTP (Mail Server 5.0.2); Thu, 11 Apr 96 20:34:53 GMT
Content-Type: text/plain; charset="us-ascii"
Status: O

******************* Please DO NOT REMOVE Version Number ********************
Domain Version Number: 2.0
**************** Please see attached detailed instructions *****************
******** Only for registrations under ROOT, COM, ORG, NET, EDU, GOV ********
0.   (N)ew (M)odify (D)elete....: N
1.   Purpose/Description........: Business Web Site
2.   Complete Domain Name.......: michweb.com

Organization Using Domain Name
3a.  Organization Name..........: MichWeb Inc.
3b.  Street Address.............: 621 N. Lake Street
3c.  City.......................: Cadillac
3d.  State......................: MI
3e.  Postal Code................: 49601
3f.  Country....................: USA

Administrative Contact
4a.  NIC Handle (if known)......: MICHWEB2.DOM
4b.  Name (Last, First).........: Simerson, Matt
4c.  Organization Name..........: MichWeb Inc.
4d.  Street Address.............: 621 N. Lake Street
4e.  City.......................: Cadillac
4f.  State......................: MI
4g.  Postal Code................: 49601
4h.  Country....................: USA
4i.  Phone Number...............: (616) 775-8416
4j.  E-Mailbox..................: matt@michweb.net

Technical Contact
5a.  NIC Handle (if known)......: MICHWEB2.DOM
5b.  Name (Last, First).........: Simerson, Matt
5c.  Organization Name..........: MichWeb Inc.
5d.  Street Address.............: 621 N. Lake Street
5e.  City.......................: Cadillac
5f.  State......................: MI
5g.  Postal Code................: 49601
5h.  Country....................: USA
5i.  Phone Number...............: (616) 775-8416
5j.  E-Mailbox..................: matt@michweb.net

Billing Contact
6a.  NIC Handle (if known)......: MICHWEB2.DOM
6b.  Name (Last, First).........: Matt Simerson
6c.  Organization Name..........: MichWeb Inc.
6d.  Street Address.............: 621 N. Lake Street
6e.  City.......................: Cadillac
6f.  State......................: MI
6g.  Postal Code................: 49601
6h.  Country....................: USA
6i.  Phone Number...............: (616) 775-8416
6j.  E-Mailbox..................:

Primary Name Server
7a.  Primary Server Hostname....: dns.michweb.net
7b.  Primary Server Netaddress..: 152.160.182.1

Secondary Name Server(s)
8a.  Secondary Server Hostname..: mail.michweb.net
8b.  Secondary Server Netaddress: 152.160.182.4

Invoice Delivery
9.   (E)mail (P)ostal...........: E

A domain name registration fee of $100.00 US is applicable.  This charge
will cover the $50.00 maintenance fee for two (2) years.  After the two
year period, an invoice will be sent on an annual basis.

The party requesting registration of this name certifies that, to her/his
knowledge, the use of this name does not violate trademark or other
statutes.

Registering a domain name does not confer any legal rights to that name and
any disputes between parties over the rights to use a particular name are to
be settled between the contending parties using normal legal methods
(see RFC 1591).

By applying for the domain name and through the use or continued
use of the domain name, the applicant agrees to be bound by the terms of
NSI's then current domain name policy (the 'Policy Statement') which is
available at ftp://rs.internic.net/policy/internic/internic-domain-1.txt.
(If this application is made through an agent, such as an Internet Service
Provider, that agent accepts the responsibility to notify the applicant of
the conditions on the registration of the domain name and to provide the
applicant a copy of the current version of the Policy Statement, if so
requested by the applicant.)  The applicant acknowledges and agrees that
NSI may change the terms and conditions of the Policy Statement from time
to time as provided in the Policy Statement.

The applicant agrees that if the use of the domain name is challenged by
any third party, or if any dispute arises under this Registration Agreement,
as amended, the applicant will abide by the procedures specified in the
Policy Statement.

This Registration Agreement shall be governed in all respects by
and construed in accordance with the laws of the United States of America
and of the State of California, without respect to its conflict of law rules.
This Registration Agreement is the complete and exclusive agreement of the
applicant and NSI ("parties") regarding domain names.  It supersedes, and
its terms govern, all prior proposals, agreements, or other communications
between the parties.  This Registration Agreement may only be amended as provided
in the Policy Statement.