CatPaw Rumors: Post Release Summary Part III

It is unexpected that CatPaw needs two refresh releases (5.1 and 5.2). But it shows a few bugs need to be addressed as soon as possible.

A few bugs only occur in our command line tools. So they are minor and do not harm the whole package. 

The biggest problem comes from our CF assembly. It is hard to make sure everything works for CF, as I am not using .NET CF anymore. Therefore, when 5.0 was shipped we can see the CF assembly is in fact broken. I was planning to fix that all in 5.1. Fixing the csproj file and adding Mono code files are relatively easy. However, something from .NET CF itself leads to side effect.

As Microsoft cut off too many things, even though Mono classes filled in some gaps, an issue happened when I tried to work around a missing String.Split method. This breaks 5.1 release, so we have to release 5.2 this weekend.

Hope you are not bothered much by these issues. If you are, please grab our latest release which contains the fixes.

http://sharpsnmplib.codeplex.com/releases/view/47894

CatPaw Rumors: Post Release Summary, Part II

Our agent, snmpd.exe, supports all three SNMP versions. Then how to get data from it?

SNMP v1 and v2c

The community strings for both GET and SET operations are the same, "public".

SNMP v3

Community names are obsolete, so snmpd.exe supports three users (to match three modes).

• "neither" is the user for noAuthNoPriv mode. If you use it, remember to use default authentication provider and default privacy provider.
• "auth" is the user for authNoPriv mode. It uses MD5 authentication provider whose phrase is "authentication". Its privacy provider is still the default one.
• "privacy" is the user for authPriv mode. It uses MD5 authentication provider whose phrase is "authentication", but its privacy provider is the DES privacy provider whose phrase is "privacyphrase".

Now let's see if you are going to test out snmpd.exe using our command line tools what commands should be used.

SNMPGET

For SNMP v1 and v2c, typical command is

snmpget -v=1 -c=public localhost 1.3.6.1.2.1.1.1.0

For SNMP v3, typical command is

snmpget -v=3 -l=authPriv -a=MD5 -A=authentication -x=DES -X=privacyphrase -u=privacy localhost 1.3.6.1.2.1.1.1.0

SNMPSET

For SNMP v1 and v2c, typical command is

snmpset -v=1 -c=public localhost 1.3.6.1.2.1.1.6.0 s Shanghai

For SNMP v3, typical command is

snmpset -v=3 -l=authPriv -a=MD5 -A=authentication -x=DES -X=privacyphrase -u=privacy localhost 1.3.6.1.2.1.1.1.0 s Shanghai

SNMPBULKGET

For SNMP v2c, typical command is

snmpbulkget -v=2 -c=public -Cr=10 localhost 1.3.6.1.2.1.1.1.0

For SNMP v3, typical command is

snmpbulkget  -v=3 -l=authPriv -a=MD5 -A=authentication -x=DES -X=privacyphrase -u=privacy -Cr=10 localhost 1.3.6.1.2.1.1.1.0

SNMPGETNEXT

For SNMP v1 and v2c, typical command is

snmpgetnext -v=1 -c=public localhost 1.3.6.1.2.1.1.1.0

For SNMP v3, typical command is

snmpgetnext -v=3 -l=authPriv -a=MD5 -A=authentication -x=DES -X=privacyphrase -u=privacy localhost 1.3.6.1.2.1.1.1.0

SNMPTRANSLATE

Typical command is

snmptranslate 1.3.6.1.2.1.1.1.0

SNMPWALK

For SNMP v1, typical command is

snmpwalk -v=1 -c=public -m=subtree localhost 1.3.6.1.2.1.1

For SNMP v2c, typical command is

snmpwalk -v=2 -c=public -Cr=10 -m=subtree localhost 1.3.6.1.2.1.1

For SNMP v3, typical command is

snmpwalk -v=3 -l=authPriv -a=MD5 -A=authentication -x=DES -X=privacyphrase -u=privacy -Cr=10 -m=subtree localhost 1.3.6.1.2.1.1

(Update: Two more bugs were found and fixed during the authoring of this article. So we will refresh CatPaw again, and it should be 5.2.)

CatPaw Rumors: A Quick Way to Build Against .NET 4

Dotnet4
Originally uploaded by lextm

Starting from 5.0 release, you can build #SNMP thing against .NET simply via command line.

The trick on Windows is like this,

1. Open a Visual Studio 2010 command prompt and navigate to the folder that contains sharpsnmplib.sln.
2. Execute

msbuild sharpsnmplib.sln /p:TargetFrameworkVersion=v4.0

Then all resulting assemblies are linked against .NET 4 version of mscorlib.dll, and so on.

This is much easier than opening all csproj/vbproj files and modifying them. Right?

Of course, this trick applies to our upcoming 6.0 release, HoneyCell.

No More Comments on This Blog

I lost access to Blogger console due to the great firewall of China Mainland, so the net effect is no more comments can be approved by me.

Until a time such blocking is removed, I don't have a way to change it.

Sorry for the convenience. You can always reach me via my mailbox, lextudio@gmail.com

IIS 7 and WSUS on Windows Server x64

It is common to see people install IIS and WSUS on the same box. However, if the following conditions are met, you may come across a 500.19 that's strange and hard to diagnose on your own,

1. This server is running Windows Server 2008 or Windows Server 2008 R2 x64 build.
2. There are IIS application pools that allows 32 bit applications.

The error page can be similar to this one,

Module	DynamicCompressionModule
Notification	SendResponse
Handler	StaticFile
Error Code	0x8007007e

Requested URL	http://localhost:80/
Physical Path	C:\inetpub\wwwroot
Logon Method	Anonymous
Logon User	Anonymous

The root cause is easy. WSUS installer inserts a dynamic compress module into IIS 7 named xpress. This asks IIS 7 to load %windir%\system32\inetsrv\suscomp.dll.

All works fine for 64 bit application pools till you allow 32 bit applications. In the folder %windir%\SYSWOW64\inetsrv\ there is not a 32 bit version of suscomp.dll, so IIS 7 cannot load this dynamic module and reports 500.19 with error code 0x8007007e.

  ERROR_MOD_NOT_FOUND                                           winerror.h
# The specified module could not be found.

Well, how to resolve it? Depending on your situation, there can be several ways,

• Split your applications, so on this WSUS box, only run 64 bit applications.
• Find a copy of suscomp.dll 32 bit, and then copy it to %windir%\SYSWOW64\inetsrv\.
  

WSUS should ship such a 32 bit copy with it, but since it does not, you have to own a 32 bit server, and copy the dll over.

CatPaw Rumors: Post Release Summary Part 1

There are still pieces unmentioned for our 5.0 release. One of that is the future of Manager and Messenger classes.

If you dig into our latest browser implementation, you will see Manager class is no longer used there. It is kind of a sign that we will get rid of this small but useful class in real world applications.

Manager was one of the early classes present in #SNMP library as it was a nice way to encapsulate all manager side functions into it (Level 3). However, soon we noticed it does not provide enough interfaces for advanced users. Messenger was added then to provide a medium level of encapsulation (Level 2). Note that you can always make use of ISnmpMessage derived classes directly which provides the lowest level of encapsulation (Level 1).

The usage of Manager becomes less, simply because our browser goes bigger and it requires more powerful things. Similarly this applies to Listener class and the agent. Therefore, in 5.0 release we started to review the design of Manager and Listener, and accordingly actions were taken. For example, bindings were introduced into the Listener class, and listener adapters were obsolete with SNMP processing pipeline introduced. Manager will face a similar attack in our 6.0 release, and it will be refactored or redesigned.

Messenger also faces demanding requests of changes. For example, it only supports v3 WALK now, and no more v3 related interfaces are yet added. So simply speaking if you are doing SNMP v3 with #SNMP, you can only use our Level 1 interfaces. How to find a set of Level 2 interfaces who are easy to use? How to bring something new to our Level 3 interfaces?

5.0 release was a nice milestone for #SNMP, as we found new approaches to do SNMP v3 better compared to old releases. But we were not able to make v3 support easier to use from API aspects. That becomes our focus on 6.0 release and wish something wonderful is there in front of us.

Well, finally leave you a few points to pay attention to,

1. Check out our samples to see how Level 1, 2, 3 interfaces are in use. For advanced users, please master our Level 1 interfaces as you usually need them.

2. For SNMP v1/v2c centric applications, if you want to migrate them to support v3, you must heavily utilize our Level 1 interfaces for v3. This can be hard as our own samples show, but it is doable.

3. For everyone, please post questions/provide feedback via our discussion board.

Stay tuned.

HoneyCell Drops: Now Comes 6.0 Codename for #SNMP

For #SNMP, the codenames for every releases implicitly contain the release numbers. Now comes HoneyCell, our next release (6.0).

For a very long time, we have done little on the compiler side. It has been asked several times that whether we will enhance it to provide more features. And now the answer is loud and clear. Yes, we will do something in this release.

First, we will try to extract more information from MIB documents, such as object description and so on. Second, the browser will display such information to the users. Third, we will use the compiler to compile MIB documents to C# classes so that extending our agent becomes easier.

The three items above may sound not too much, but once we are able to ship it, you will see how amazing it can be.

Besides, we will review all possible areas to improve the library and other parts along the way.

Stay tuned.

LeXtudio Fund: Initial Thoughts

I run a few open source projects under the title of LeXtudio. In the first few years all of them did not bring me any money. But my job at Fortune 500 companies (Cisco Systems/Microsoft in the past, and Morgan Stanley now) gives me enough to afford living in the most expensive (Shanghai) city in China, and now I even want to buy a small apartment this year.

But recently CodePlex (http://codeplex.com) collaborates with the Lounge (http://www.theloungenet.com/) and I can publish ADs on the project pages. As a result, a small amount of money can be received every year (40 USD approximately). So the projects start to make money.

I do have received two donations, one from Michael Giagnocavo (€3*.**) back in Aug 2008, and the other from Andrea Bertolotto ($1**.**) in this month. I have to say they sent me a lot compared to what I imagined. I really appreciate their generous offer.

Then how can I make good use of all the money received from the open source projects? I am still trying to figure out what can be the best way(s). So today, this post simply announces that I put the money into a fund (LeXtudio Fund). I will provide more details when I start to make use of it.

Stay tuned.