Netgear AC750 Wifi Range Extender (EX3700)
Here is how I satisfied my need to have a LAN messaging program, not really to chat with other users on the same LAN, which I could do, but to copy and paste links or texts between a rdp client and a rdp server when copy and paste from/to clipboard does not work in rdp sessions, for instance with some Android rdp clients.
These are the programs I used:
- Openfire 3.9.3 on the "server" (which can be a simple Windows pc): a realtime collaboration server using XMPP/Jabber
- Miranda IM 0.10.23.0: a multi-protocol instant messaging client
- Xabber 0.9.30b: an Android Jabber client
Create a VPN to connect from an Android client to a home Windows XP server
If you want to connect to your home computer using rdp when you are not home and are connected to the internet, you have to open a port on your firewall; changing the standard rdp port on both your server and your firewall increases your security (or decreases your unsecurity); configuring a Virtual Private Network (VPN) increases your security even more, and you can close the rdp port on your firewall: in fact, when you connect your remote client to your vpn, your remote client comes inside your LAN so that you can remote access your server from inside the LAN.
- Configure server to create a VPN
- Configure router firewall for VPN passthrough
- Configure VPN on Windows clients
- Configure VPN on Android devices
.htaccess: an example of the Apache per-directory configuration file
Using bloxsom as my weblog designing application, I had to provide some settings to the Apache
.htaccess configuration file to fine-tune the usage of my site:
- tell Apache to load
index.cgiin addition to the default
- rewrite the requested address adding
www.if it's omitted
- rewrite the requested address adding
index.cgiif it's omitted
- and for bandwidth reduction, forbid robots from crawling some pages
How to force Firefox to open in a new tab a link that tries to open a new window
about:config in the address bar, read the warning and confirm.
Then change the value of
browser.link.open_newwindow.restriction to 0.
See mozillazine about:config FAQ for a detailed description of the variables and values.
With my LCD monitor, a LG 1718S, the characters appear too much narrow on the screen, especially using Excel sheets: I tried all OSD settings but the characters are so much thin that they're almost invisible. I got the best results setting the ClearType effect:
Control Panel, Display, Appearance, Effects, Use the following method to smooth edges of screen fonts: Clear Type
This way the characters appear a little fatter and they're better looking too.
Yes, I use light grey background color :)
This 3Com product has many functions: router, firewall, adsl modem, wireless access point, 4 port switch. 3Com chose to give two names to its products: a name for the market (as the long name in the title), which identifies the purpose of the product and is not changed when a new model replaces the older one, and a model name, a number which identifies the specific model.
The "ADSL" term in the name is particularly useful to specify that it's a adsl modem too, with a RJ-11 port that would connect the router directly to the phone line, through a RJ-11 cable, just like any adsl modem; in fact I found several routers that were capable of routing the adsl signal but were equipped with a RJ-45 port instead of a RJ-11 port: they were not DSL modems and needed to be connected to an external DSL modem. Checking the rear of the product, maybe on the user guide, can help making sure the router is a DSL modem too.
I will review two 3Com OfficeConnect ADSL Wireless 54 Mbps 11g Firewall Router models, the older 3CRWDR100A-72 and the newer 3CRWDR101A-75.
- Reliability and 3Com assistance
- Wireless trouble with 3CRWDR101A-75
- Wireless coverage
- Other features
- Missing features
Recover "Logical sector size is 0" with dd
A few hours ago while I was using my pc suddenly Windows froze completely (mouse was stuck and Ctrl+Alt+Del did nothing). It's not astonishing but I was quite surprised because such a freeze never happened since I began using Windows XP on my new pc.
The problem appeared at the reboot:
grub, the bootloader on /dev/sda, showed this error message:
At reboot I started Windows XP Recovery Console from the Windows CD and tried
CHKDSK.EXE, and this was the outcome:
I booted again linux to launch
fsckand see it fail:
Then I found the solution in ubuntu forum:
root@am2:/home/z24# dd if=/dev/hda1 of=/defmedia/bkup_fat32_hda1.img bs=512 count=2048000 conv=noerror,sync 2048000+0 records in 2048000+0 records out 1048576000 bytes (1.0 GB) copied, 43.61 seconds, 24.0 MB/s root@am2:/home/z24# dd if=/defmedia/bkup_fat32_hda1.img of=/home/z24/sector6.bin bs=512 count=1 skip=6 conv=noerror,sync 1+0 records in 1+0 records out 512 bytes (512 B) copied, 0.011544 seconds, 44.4 kB/s root@am2:/home/z24# dd if=/home/z24/sector6.bin of=/dev/hda1 bs=512 count=1 conv=noerror,sync,notrunc 1+0 records in 1+0 records out 512 bytes (512 B) copied, 0.030644 seconds, 16.7 kB/sExplanation:
- the first dd makes a backup of the first gigabyte of the Windows partition: I copied 1 GB only because I didn't have enough space on a ext2fs to backup all the 28 GB of /dev/hda1.
- the second dd extracts the sixth sector to a temporary file: as reported by Microsoft KB247575, "The backup FAT32 boot sector is located at sector 6 of the logical drive".
- the third
ddcopies the extracted sector 6 to sector 0 of /dev/hda1.
ddwas also checked with
mount. Thanks a lot to the ubuntuforums user Onlymee for his post!
Update 13.09.2008The same problem happened again today and gave me the opportunity to complete the series of error messages :)
The first, at boot time, was the same: Mounting the partition (
mount -t vfat /dev/sda1 /mnt):
dmesg | grep sda1But
fdisk -l /dev/sdashows the partition table.
fsck.vfat /dev/sda1(executed from Ubuntu 8.04 alternate cd) The solution was exactly the same: copy the sixth sector back to the first. And voilà, it booted.
Accessing and changing the registry from outside Windows
Problem: I got myself locked out of my pc
Solution: access the registry from outside Windows and change the account lockout settings
After enabling Remote Desktop access to access from my notebook to my pc through my wireless LAN, I was playing around with account locking settings to defend from possible brute force attacks coming through the WLAN (supposing the attacker cracked the WPA-PSK password): I set the lock so that after two failed attempts to login the account would be locked until the administrator (me) unlocks it manually.
I wanted to adopt such a security measure for RDP access only, but unfortunately the account lockout policy is valid for any login attempt, being it local or remote.
Then, as a slight security measure, I also disabled the administrator user (my user is already an administrator and an attacker should also find a valid username).
I mistyped the password twice and I got myself stuck: administrator and guest were disabled and my account was locked.
After rebooting, at the logon screen there were no more users, so that the "To begin, click your username" sentence on the left sounded like a joke, having absolutely nothing on the right.
The solution was obvious:
- try to access and change the registry from linux (I have dual boot)
- manually restore a previous version of the registry
I solved using Offline NTPassword & Registry Editor, an offline regitry editor on a boot disk; I made the floppy, rebooted and then I started looking in the registry the affecting keys, but it was not necessary: there's a feature to edit the accounts, and that allowed me to enable the administrator.
I also found dumphive, a useful program to dump the registry hives to text files.
Instead on www.beginningtoseethelight.org there's plenty of Windows NT, 2000 and XP low level settings and hacks, I would say "all about the registry": for instance, where and how users and passwords, including account statistics and policies, are stored and encoded in the SAM hive of the registry, and a schematic explanation of the registry structure; and don't miss the other sections of the site, they're enlightening too.
About the second option, there's a Microsoft article that explains how to manually restore the registry to a previous state.
I'll try to answer these questions:
- What is AMD Cool'n'Quiet?
- Does it really work?
Remove XP Pro or Win Server 2003 bandwidth limit
Run Group Policy (gpedit.msc) and go to Computer Configuration -> Administrative Templates -> Network -> QoS Packet Scheduler and change "Limit reservable bandwidth" to "Enabled" with a value of 0%. By default it appears disabled but read the description and you'll discovered it's enabled with a value of 20%.
Seeing MySQL queries, just like MS SQL Profiler
Just execute mysqld with the
-l[=filename] command-line option.
If filename is omitted, hostname.log will be created in the mysql data directory.
log=filename line (i.e. if you use WAMP).
Then restart mysqld.
Blosxom: How to insert a fixed path for images in Blosxom
I wrote some post on my new site created with Blosxom and I wanted to insert some images that I put in a directory called
images under my website address root.
I found different solutions:
WAMP & Perl - Windows Apache, MySQL, PHP with CGI scripts written in Perl
I need Perl to run Blosxom, an open source and free CGI script to create blogs.
So I installed WAMP5 1.6.4a and ActivePerl 126.96.36.1997 with MSI installer.
I already have my site on my disk, so I told my site directory to WAMP during the setup procedure and then I pointed my browser to http://localhost/index.cgi but it displayed the cgi instead of executing it.
This is what I did to make it work:
Running PHP scripts from command-line with WAMP (Windows Apache, MySQL, PHP)
On my old pc I installed Apache, MySQL and PHP singularly, and I made some PHP scripts to be runned from command-line, like this:
c:\php\php -f myscript.phpOn my new pc I installed WAMP5 1.6.4, all was running fine (phpMyAdmin, my local website, php scripts pointed to by the browser) but php scripts launched by command-line reported
Fatal error: Call to undefined function mysql_connect() in myscript.phpObviously I changed the php path to
c:\wamp\php\phpbut with no results.
Solution: change the command to
c:\wamp\php\php -c c:\wamp\apache2\bin -f myscript.phpThe -c option tells php to search php.ini in the directory specified, and that's needed because WAMP puts php.ini in Apache bin directory, while with a PHP regular installation php.ini is located in the php.exe directory.