A site devoted to discussing techniques that promote quality and ethical practices in software development.

Wednesday, June 30, 2010

No joy being (mis)classified as a bogon!

About a week ago, I tried to access http://www.translink.com.au, the integrated public transport for South East Queensland, and my browser timed me out unable to reach the site and since then I cannot access that site. Over this period and preceding that, I have not changed any router settings.

A tractrt brought me this typical result:
Tracing route to www.translink.com.au []

over a maximum of 30 hops:
1 2 ms 1 ms 1 ms 192-168-1-1.tpgi.com.au []
2 24 ms 24 ms 24 ms
3 24 ms 24 ms 24 ms 202-7-165-1.tpgi.com.au []
4 25 ms 24 ms 24 ms bri-sot-wic-crt2-po1.tpgi.com.au []
5 41 ms 42 ms 41 ms syd-sot-ken-crt1-TG-7-0-0.tpgi.com.au []
6 42 ms 41 ms 41 ms 202-7-162-246.tpgi.com.au []
7 59 ms 59 ms 59 ms []
8 59 ms 59 ms 59 ms []
9 * * * Request timed out.
10 * * * Request timed out.
11 * * * Request timed out.
12 * * * Request timed out.
13 * * * Request timed out.
14 * * * Request timed out.
15 * * * Request timed out.
16 * * * Request timed out.
17 * * * Request timed out.
18 * * * Request timed out.
19 * * * Request timed out.
20 * * * Request timed out.
21 * * * Request timed out.
22 * * * Request timed out.
23 * * * Request timed out.
24 * * * Request timed out.
25 * * * Request timed out.
26 * * * Request timed out.
27 * * * Request timed out.
28 * * * Request timed out.
29 * * * Request timed out.
30 * * * Request timed out.

Trace complete.

Initially I thought the site might have been down but asking several friends to test reach this site told me the site was up and running. While some using the same ISP as mine, TPG, met with the same fate. A search on the Internet resulted in a thread in a broadband forum discussing this very issue for users on TPG, my ISP, meeting the same fate.

My fate apparently is the result of me, by virtue of my IP address, being a bogon. It is no joy because essentially I cannot do anything as I do not control the IP address allocation. Furthermore, when things like this happening, there is no one-stop shop where you can go to get help and no one authority having the power to arbitrate. The ISP giving me the IP address is not really responsible for my fate; I guess in some way they are responsible for allocating a bogon IP to me. The destination party may be slow to the bogon's classification update announcement to correct the filtering problem resulting my mis-classification. That party may not even understand or aware that they are doing bogon filter using outdated data. Have you ever tried to discuss this kind of technical details on a site's feedback page, if one exists?

This site is of great importance to me as I routinely perform legitimate e-commerce transactions on it to top up my transport stored value smart card. Failure to access this will mean that I have to top up by queuing up at top up stations denying me the convenience e-commerce brings.

Thankfully at the moment, I have two ways to reach this site beating the alleged bogon classification. One is to use a proxy server like http://freeproxyserver.net. The other technique is to use a Tor Browser, which is my preferred way to access this site.

Just to prove that there is nothing wrong with my internet connection and router settings, here is a screen shot showing the successful connection to Translink, showing on the left using Tor Browser, and the failure screen via direct connection using my ISP allocated IP address, shown on the right. The two browsers are running simultaneously.

When using IE8, the message return is that it cannot display the page like this:

Perhaps there is another explanation other than me being a bogon! Checking my IP address against a list of Blacklist Servers using whatismyipaddress.com tells me that I am not blacklisted. So is the reason?

At the moment I am in limbo with two lifelines at the mercy of the Internet magic! If you are contemplating of implementing bogon filtering, be prepared to do frequent update as IP ranges go in and out of the bogon range. Failure will cause unwittingly innocent victims, like me, great problem. Think hard before you use bogon filter.

Saturday, June 26, 2010

Caveat is using NTBackup in Windows 7

Evaluation of several backup utilities to replace the terrible Windows 7 "Backup and Restore" facility has been reported in my previous blog.

The conclusion is that NTBackup, until a more formidable free one comes around, is still the best backup utility. What you need to run this in Windows 7 has been documented here and it also mentions that you can safely disregard a warning message box.

However, the disclosure given fails to mention one very important setting you need to turn off. That is the 'Disable volume shadow copy' in the 'Advanced backup options' dialog box here:

Make sure you check this option otherwise the back up will abort with this message:
Error returned while creating the volume shadow copy:Catastrophic failure

Aborting Backup.
Test of backing a program while still in use seem to be unaffected by this option.

Tuesday, June 22, 2010

In search of a Backup Utility for Windows 7

While people reading this title may be wondering if I have missed the much touted "Backup and Restore" features in Windows 7 and wondering why I need to search for (better) Backup Utility?

Let me describes the deficiency in Windows 7's "Backup and Restore" utility before I will describe my search result.

Microsoft has succeeded in taking a highly capable program called NTBackup and destroying it for the sake of some eye-candy screen. The Win7 backup is so slooooow that any ZIP program will beat it hands down. Not only that, the eye-candy stuff lacks any really useful progress information. It does not even bother to tell you how many files it has picked up, which file is processing, and the total size of the files being backup (until the whole thing is finished) or expected time to take, given that is a best-guess. Apart from some pretty looking screens, the user-interface is totally unintuitive and functionality lacking.

If you have not seen an industrial strength real back up utility, I suggest you fire up a copy of NTBackup in XP Pro or installed it in Home Edition.

One of the basic needs of a back up utility is to be able to add the back up information to what is already there like keeping revision so that you can go back several generations to restore the data.

Not only that a backup utility is as good as its restoration capability. It has to be able to restore the data accurately and precisely including restoring the original ACLS for the NTFS files and folders. Failure to do that can cause major problem and security risk. Imagine you are backing up the profile areas for a machine and has to do a disaster recovery only to discover that the resulting ACLS are all wrong!

A good backup utility also should ensure that the person running this must be a backup operator or one with the SeBackupPrivilege, to perform backup and SeRestorePrivilege, to perform restoration.

The other features commonly found in industrial strength backup utility is to be able to perform incremental backup so to reduce the backup volume. This is important when you are doing a daily backup.

Armed with these demands, I evaluated the following free backup programs: NTBackup, FBackup, and Comodo Backup.

Sadly only NTBackup managed to perform flawlessly managing to replicate the ACLS perfectly. Here is a screen shot of the source (left hand window) and restored folder's ACLS (right hand window):
I restored the material to a different directory to check the restoration process. As a consequence, NTBackup is being used as a benchmark against which the other utilities are compared.

FBackup4 Version 4.4 Build 207
This is a very simple to use free 'backup' utility. The good part of this one is its ability to manage several backup instructions as jobs in the program. It automatically increments the backup volume file name and the backup volume is in ZIP format. It is relatively fast.

However, it is a naive implementation of a backup utility. At best, it can only be classified as a ZIP program with a purpose-built user-interface.

Here is the screen shot of restoring the user's profile to an alternate location. Once again the left hand window shows the security settings of the original top level user profile folder and the right hand window shows that for the restored materials:
This clears shows the restored materials have fewer privileges than the original materials failing being a competent back up utility. This is a simulation of profile restoration.

Comodo Backup Version 2.2.127000.12
The user-interface is prettier than FBackup but it is also more confusing and functional lacking. With its user-interface, a user cannot workout how to get the program to remember the backup instructions so that one can reuse them again. However there are several ways this program that this program can do that, albeit not as intuitive as that for FBackup.

During the composition of the backup instruction using the wizard, you can use the Schedule definition to remember your instructions even if you do not want to do scheduled backup. You simply change the type to manual backup. Strange logic.

The other way is to export your backup instructions to a file which contains the command-line arguments corresponding to your instructions. With this file you can then use the /script command-line directive to supply the script file when launching the backup utility.

This utility has some slick facility allowing you to define the backup volume file format - such as including date, time etc. They call them macros and they are not available in FBackup. It also has facility for you to define the level of compression you want during backup.

Performance of this program is very good. However it suffers the same problem as in FBackup when it fails to reproduce precisely the ACLS as shown below:

These backup utilities are not really backup tools but specialized ZIP programs. It is not just because they are using ZIP format but because they left out the ACLS what they need to use to restore them

While NTBackup is available official in XP Pro and optionally in XP Home Edition, Microsoft has provided a cut-down version of this tool for Vista/Windows 7, called "Windows NT Backup - Restore Utility", so that user can restore from NTBackup volumes.

However, NTBackup has been known to run fine in Vista and in Windows 7 (and here). Since the 'installation' of NTBackup is so low impact, I will definitely give that a try. The big remaining question is: At what time in the future that Windows development will render our trusty friend not operable?

Sunday, June 20, 2010

Virtual Machine software on Windows 7

Ever since Vista promoted that multiple level license pack - Home Edition, Professional/Business, Ultimate - Microsoft has been flagging certain programs "not supported" on cheaper edition.

This form of money grabbing exercise continues with Windows 7. Not contended with this, Microsoft actually turns up the confusion one more notch by introducing Windows Virtual PC as oppose to Virtual PC 2007 SP1.

Windows Virtual PC works fine with VM created in VPC2007. But one thing to remember, you cannot run Windows Virtual PC together with VPC2007sp1 on the same Windows.

When you install VPC200SP1 (just make sure Windows Virtual PC is uninstalled - go to 'Programs and Features' and then 'Turn Windows features on or off') on Windows 7 Home Edition, Windows will warn you that the program is not supported on this edition of Windows. Just ignore this as it works fine. It is Microsoft's way of tricking you to buy a more expensive edition. Read on for more virtual machines that do not practice this kind of scare tactic.

While running Windows Virtual PC, drag-drop from Host OS to Guest OS or vice versa does not seem to be working while VPC2007SP1 handles this operation without trouble. If you like the drag-drop feature, just use VPC2007SP1, which incidentally supports wider guest OS.

When running up the VPC2007SP1 console, it will display this lame warning message box:
Just ignore this.

If you are concerned by this, check out this comprehensive review of other Virtual Machines available that are not concerned with which edition of your Windows 7 or Vista you are running on.

It is actually better to run non-Microsoft Virtual Machine because in this way you are guarantee a uninterrupted migration path to non-Microsoft Host OS machine. It is also interesting to note that VirtualBox can run 'XP Mode' VM.

After exploring these confusing situations, I have settled on using VM Player for serious stuff and to benefit from a much wider support of guest OS, leaving VPC2007SP1 to deal with my experimental VPC VM that I have accumulated.

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