Advanced SSH security tips and tricks
Linux.com has a nice article covering some tips and tricks on advanced
SSH security.
Friday, August 24, 2007
Advanced SSH security tips and tricks
Sunday, August 19, 2007
Antenna Design
Pringless Cantenna
Pringless Cantenna
Parts list:
| All-thread, 5 5/8" long, 1/8" OD | |
| two nylon lock nuts | |
| five 1" washers, 1/8" ID | |
| 6" aluminum tubing, 1/4" ID | |
| A connector to match your radio pigtail | |
| 1 1/2" piece of 12 gauge solid copper wire | |
| A tall Pringles can | |
| Scrap plastic disc, 3" across | |
| |
Tools required:
Ruler
Scissors
Pipe cutter (or hacksaw or dremel tool, in a pinch)
Heavy duty cutters (or dremel again, to cut the all-thread)
Something sharp to pierce the plastic (like an awl or a drill bit)
Hot glue gun
Soldering Iron
Construction time: about an hour
Front collector construction:
Mark and cut four pieces of tubing, about 1.2" (1 15/64"). Where did I get this number? First figure out the wavelength at the bottom of the frequency range we're using (2.412 GHz, or channel 1). This will be the longest that the pipe should be:
W = 3.0 * 10^8 * (1 / 2.412) * 10^-9
W = (3.0 / 2.412) * 10^-1
W = 0.124 Meters
W = 4.88 inches
We'll be cutting the pipe to quarter wavelength, so:
1/4 W = 4.88 / 4
1/4 W = 1.22"
Now figure out what the shortest we'll ever use is (2.462 Ghz, or channel 11 in the US):
W = 3.0 * 10^8 * (1 / 2.462) * 10^-9
W = (3.0 / 2.462) * 10^-1
W = 0.122 Meters
W = 4.80 inches
1/4 W = 1.20"
Thursday, August 16, 2007
Resources for Running Solaris OS on a Laptop
- Multi-Booting the Solaris 10 OS, Linux, and Microsoft Windows on a Laptop
- Configuring Multiboot Environments on Sun x64 Systems with AMD Opteron Processors
- Solaris 10 Quick Install on x86/x64 Systems
- Multi-booting Solaris and Other Operating Systems
- OpenSolaris Laptop Community
- GRUB and the Solaris 10 1/06 OS: The New Bootloader for x86 Platforms
Ask the Expert: How to jump into a rocky stock market
Tuesday August 7, 9:21 am ET
By Walter Updegrave, Money Magazine senior editor
Question: I'm 28 years old and looking to invest some extra money that's come my way recently, $10,000 to be exact. Any suggestions? - Brandon, Charlotte, NC
Answer: It's always a challenge trying to figure out the best way to invest a windfall. But the task is even more daunting when you're dealing with a roller-coaster market like the one we've had in recent weeks, where big sell-offs are followed by hopeful rebounds that give way to more unsettling down-drafts, creating a climate of fear and uncertainty all around.
So I'm happy to weigh in on this issue. I'll try to answer in a way that can also give guidance to others out there who are unsure how to navigate a market like this, whether they're investing new money like you or considering what to do with the money they've already invested.
The first thing I think you need to do is be wary of some of the advice that's already floating around out there. I don't want to say much of it is flat-out bad. But I do think a lot of it is misguided.
I'm thinking not just of the obligatory stories recommending you move your money to "safe harbors" like money-market funds and bonds or that you buy "defensive stocks" that are supposed to shelter you from losses, but also their opposite counterparts. You know, the ones that say now is the time to start scooping up bargains by buying on the dips.
In both cases there's a presumption that you know what lies ahead - that is, that the market is headed down further and thus you need to protect yourself or that most of the damage has been done so you'll be buying in just in time to ride the rebound.
Let me be clear about this. Nobody knows where this market is headed over the short-term. And nobody can know because that will be determined not just by how things shake out in areas ranging from subprime mortgages to company earnings to inflation and interest rates, but also how investors react to those developments.
So how does one invest in the face of such uncertainty at a time when investors are also clearly on edge? I recommend you start by asking yourself the following three questions.
1. How long will it be before I need the money? This is always the first question you should ask before investing money, but it's especially important to ask it in a volatile market like today's. If you're going to need access to some of your $10,000 within, say, two to three years, then you should invest that portion of your stash in money-market funds or short-term CDs where it will be immune from the ups and downs of the financial markets.
After all, if you're depending on your money as an emergency reserve, or if you're going to need it in a few years for a house down payment or college tuition, you want to be sure the funds will be there. You don't want to risk that it will be tied up in stocks that are worth 20 percent less than you paid for them, even if those stocks may eventually rebound to big gains.
On the other hand, you can afford to take a little more risk in pursuit of higher gains if you're investing longer term, since you have more time to recover from market setbacks. The way to go after those higher long-term gains is by building a portfolio of stocks and bonds (or, more likely for most individual investors, stock and bond funds).
The key, though, is that it's your time horizon that determines the investment choice. Not some notion of what the market is or isn't likely to do in the near future or where you might find the highest returns.
2. Do I have the right stocks-bonds mix? Once you know you're investing funds you won't be touching in the short-term, you can start thinking about how to divvy up that money between stocks and bonds in a way that makes sense for you. The first issue, again, is time horizon.
The longer the money will be invested, the more you can afford to put in stocks. If you're in your 20s and you're putting money into an IRA you won't touch until you're retired, you might want to put upwards of 90 percent in stocks.
Forty years from now, a market correction that occurs today will seem like little more than a blip. If, on the other hand, you're investing money you'll need in, say, five to 10 years, you still want some stocks for growth, but not nearly as large a stake.
In deciding on a stocks-bonds mix, you also want to factor in what I call a "gut check" - that is, you want to realistically gauge how you might react if your portfolio takes a hit of 20 percent or more. There's no sense in keeping 90 percent of your money in stocks if a market meltdown would have you shedding your stock funds at fire-sale prices.
At the same time, you don't want to be such a wimp that your portfolio earns only lackluster long-term returns. Our Asset Allocator tool can give you some guidelines on how to handle this balancing act. Just answer a few questions, and you'll get a recommended portfolio mix that can serve as a starting point for creating your own blend.
You can then go to the Asset Allocator tool in the Investment Guidance & Tools section of T. Rowe Price's web site to see how different stocks-bonds allocations might do in the future. (You don't have to be a T. Rowe Price customer to use the tool, but you do have to register for the site.) Once you've settled on an asset mix, you can check out the Money 70 for fund recommendations.
If you want ease and convenience, you can simply opt for a target retirement fund that has a date that roughly corresponds to the year you'll retire. You'll get a pre-mixed portfolio with a blend of stocks appropriate for someone your age investing for the long term. If you prefer to create your own mix, I suggest you consider doing it with low-cost index funds, or at least make them the core of your portfolio and supplement the index funds with a few good actively managed funds.
3. Am I acting on reason or emotion? While at my gym last week, I was watching one of the cable TV financial shows as the market was in the midst of a steep decline. Based on the frenzied rapid-fire report of the correspondent on the trading floor, you could easily get the impression that you'd better quickly dump your stocks before you get caught in a bloodbath.
Of course, just weeks before, the same show was so upbeat when the market was hitting new highs that you could have gotten the impression you were an idiot if you didn't take out a home equity loan and plow the proceeds into the market.
All of which is to say that you've got to be careful about getting caught up in undue pessimism during bad times and irrational exuberance when things are going swimmingly. It's almost always a mistake to invest in the heat of the moment. Better to step back, calm down a bit, even let a day or two go by and then make sure that you're making a decision that reflects a long-term strategy, not some passing passion.
If you answer these three questions in a thoughtful and honest way, I think you'll come away with a good sense of how to invest any new money. And you'll also be able to assess whether you're doing the right thing with whatever funds you already have invested.
I can't guarantee, of course, that this approach will immunize you from losses. There's no way to do that, if you want to earn decent returns. But at least you'll know you're making your decisions in a consistent and rational way, and that you're lowering the chances of compounding the losses from a market setback by inflicting even more damage of your own.
Monday, August 13, 2007
HPUX
mau check how many bits? mode mana working on 32-bit or 64-bit
getconf KERNEL_BITS
locale info main nyorok2 dalam?
/usr/lib/nls/README.nls.10.0
To Copy sw depots from a remote system
swcopy -s
eg:
swcopy -s dumpy.abc.com:/swdist/IPF/mentibang-laut-source @ kaldai.abc.com:/kaldai
install software from a remote machine
swinstall -s
Example:
swinstall -s cipan.abc.com:/home/cipan/add_to_be/11.00/aCC.3.37.01.depot
nak list entries : swlist -s
nak preview installing software : swinstall -p -s
bedal install the software : swinstall -s
Enable/disable file system mounting for swinstall
swinstall, like HP-UX, assumes that every mounted disk is crucially
important to the running of the system. If it isn't important, it
should not be mounted. You've probably already seen the hangs with bdf
and logins when an NFS servicer fails. You can override the requirement
that everything in /etc/fstab must be mounted with the swinstall option:
-x mount_all_filesystems=false
nak create shared library in HPUX
cc -b +z test.c -o libtest.sl
+z - Generate Position Independent Code (PIC)
-b - Generate shared library
8. To find out machine information
Use the command:
/opt/ignite/bin/print_manifest on IA or PA
Only on IA
machinfo
nak check physical memory
a) grep Physical /var/adm/syslog/syslog.log
Works for any user
b) /usr/sbin/dmesg | grep Physical
untuk root
To tune kernel paramaters
Use /usr/sbin/kmtune OR
/usr/sbin/kctune
Tuning network paramaters
------------------------
- tcp_time_wait_interval
Set the value to 1 second:
# ndd -set /dev/tcp tcp_time_wait_interval 1000
- tcp_fin_wait_2_timeout
Set the value to 10 minutes:
# ndd -set /dev/tcp tcp_fin_wait_2_timeout 6000000
These settings need to be defined whenever the system is re-booted.
To do this update /etc/rc.config.d/nddconf with the required
parameter as shown in the following example:
TRANSPORT_NAME[0]=tcp
NDD_NAME[0]=tcp_time_wait_interval
NDD_VALUE[0]=1000
TRANSPORT_NAME[1]=tcp
NDD_NAME[1]=tcp_fin_wait_2_timeout
NDD_VALUE[1]=600000
Why do I get a malloc error during swremove?
* Session selections have been saved in the file
"/.sw/sessions/swremove.last".
ERROR: "hpomt1:/": Could not allocate memory on this remote host
during task initialization, analysis or execution -- malloc()
failed.
* The analysis phase failed for "hpomt1:/".
* Analysis had errors.
While removing softwares, the following two rules must not be broken:
1. no patch left on the system without its base
2. under a no-rollback situation, a patch cannot be removed without also removing its base.
this generally happens if a path removal is tried after removing Base product
To remove a particular revision when multiple revisions are present
To remove a particular revision of software, when multiple revisions are present:
swremove
eg: swremove keldai,r="4.51.000"
How can I change the timezone?
The timezone is dtermined by reading the 'TZ' environment variable.
This variable is set when you execute 'set_parms timezone'. Set_parms
edits the file '/etc/TIMEZONE,' which exports the 'TZ' environment
variable. When you reboot after executing set_parms, the file
/etc/TIMEZONE will be read and your TZ variable set to the value you
specified. The value is in the format:
[:]STDoffset[DST[offset][,rule]]
For example: PST8PDT for the U.S. Pacific Time Zone
See the environ(5) manpage for a detailed description of the format.
Note, the offset for daylight savings time is supplied by the
'/usr/lib/tztab' configuration file.
libc functions like ctime use the 'TZ' variable to determine the
To Fix the compiler crash with error
Error (internal problem) 7108: Exact position unknown; near ["../../test.cpp", line 1033]. # The value 0x22ec did not fit into a signed 14 bit field at offset 0x99dc (op code - MOVB) (7108)
Apply patch: PHSS_29483
16. Downgrading a software
swinstall -x allow_downdate=true -s $PWD/
Sunday, August 12, 2007
Nothing much that i do today.. as usual, i was on-call for last night and worked until morning at 8.30.Then went back to my apartment at Damansara drop by near food stall bought some food and cigarettes.kinda sleepy.. so after eat, had a smoke.. while waiting for the food to be digest :) then daaabossh.. i slept until 5 and woke up.. took a bath.. straight went to jusco to to buy some ingredients to cook for tonight.. end up buying some pregio spagetthi and a bottle of pregio spagethi Garlic and onion sauce.So cooked and eat.. while watching some sort of new show on TV3 called bang bang boom and then called up Ieda.. chit chat a while.. then.. here i am.. at the office again :). no idea .. what to blog.. oh yaa.. tommorow gonna try the self service laundry shop at my place.. that was recommended by syg.. .. gonna check it out..
ok.. gonna chow.. cyaaa..
I'M STILL ALIVE!
salam to my blog that i have left for such a long time... just want you to know that youre not being abandoned.It just that i have stop blogging for a while in a search for a happiness in my work , my life.During the process i have started back blogging ... not at blogspot.. but 360.So perhaps i will start continuing blogging back at the first blog that ive started blogging.This is going to be my new chapter of my life.Alhamdulillah i thanked you Allah for still letting me live up until now to pursue my dream and happiness.I thanked you for that.. Allah hu a'kbar.
salam to my blog that i have left for such a long time... just want you to know that youre not being abandoned.It just that i have stop blogging for a while in a search for a happiness in my work , my life.During the process i have started back blogging ... not at blogspot.. but 360.So perhaps i will start continuing blogging back at the first blog that ive started blogging.This is going to be my new chapter of my life.Alhamdulillah i thanked you Allah for still letting me live up until now to pursue my dream and happiness.I thanked you for that.. Allah hu a'kbar.
