People tend to think that gone are the days when the “RPM Hell” used to exist. We have yum, aptitude and what not! If you install linux on a PS3, I’d like to bring you back to reality, especially like me when you have yellowdog 5.0 installed on a first gen PS3.
What is interesting is that all these package managers rely on repositories in /etc/yum.repos.d/*.
If you do not have the good repositories then you can kiss goodbye to installing the Cell Broadband Engine SDK provided by IBM. This SDK has the spu-gcc, spu-g++ which is the right set of compilers if you want to use the 1 master processor (Power Processor Element – PPE) and the other six SPE (Synergistic Processor Elements – SPEs) …think of these as slaves. You might wonder where’s the 7th of the cell processor, well, you cannot access it because it is used internally by the PS3 for virtualization.
So I got a yellow dog 5.0 iso image from here. I followed the instructions for installing it from here. I did this almost a year ago! Yes…I did actually keep it dead for a while! Then I installed gcc and compiled John the ripper! To my utter disappointment, there was no performance benefit!
Then Marc Bevand told me at Toorcon X that I needed spu-gcc to compile JTR on PS3 to get the benefits. So I got the cell sdk ISO from here. I then mounted the ISO.
mount -o loop cellsdk11.iso /mnt/disk
cd /mnt/disk
cd software
./cellsdk install
I got bunch of errors. It wanted me to install freeglut-devel and tk-8.4.*.
Thus began my journey of 10,000 steps to get the dependencies resolved and I burnt my fingers, keyboard, brains, etc….and although I realized that everyone in the US and the world had found hope…things were not looking bright for me! Until I bumped into this fantastic repository here. Trust me it took me about 8 hours of incessant installing and compiling (almost 120 odd different files) and scores of google searches to land me into this. I installed the glut, libx11, tk, tcl, libtcl, glut-devel, libstdc++, libstdc-so7, and many other packages that I cannot even recall now to get the cellsdk to work! And even though I did, I still couldnt get ./cellsdk install to work! After about 8 hours of effort and being so close to success just seemed evil. Then I realized that all the packages needed were related to the PPC64 simulator (libx11.ppc64, libtcl.ppc.64, etc.)…a quick look into the readme told me that I could neglect that using the –nosim directive to make it work.
Finally,
./cellsdk install –nosim
worked!!!!!
A small step for mankind but a giant step for me!

Ever since I installed Tortoise SVN I saw that the right-clicks on my Windows XP SP2 had been terribly slow. It seems like Tortoise performs a whole lot of caching. Every time you right click all the cache entries are browsed and updates are sought. Although, the interface provides ways to disable this overlay caching, it seemed to me that the caching was being performed regardless. I had to uninstall the client to restore the sanity of my right-clicks. I guess software designers should make design decisions such that the UI responsiveness is not compromised for Windows Shell extensions.

Using watermarks in word documents looks really cool. But the problem occurs when the documents become too big. In such cases, the document becomes exceedingly slow to react to scrolling. Adobe PDF conversion is an even bigger problem.
To remove the watermark it is simple enough : Format -> Background -> Printed Watermark. Then click on “No watermark” and you are golden (or you should be golden).
I’ve observed that the watermark does not get removed many times when you have too many sections in the document.
In such cases: Goto View -> Header and Footer. Click on “Show/Hide Document Text”.
You should see that all your text has disappeared except the watermark. Click on the watermark and you should be able to select it like a floating image. Press the “delete” key and lo! behold! the watermark is gone.
This took me a while to figure out and it was quite frustrating. I hope this post helps someone!

Sometimes simplest of the errors get you bad….and this was one such time.
I was trying to connect to my Oracle XE DB using SQL*Plus but kept getting this errror

connect hr/************
ERROR:
ORA-01034: ORACLE not available
ORA-27101: shared memory realm does not exist

Turns out I did not start the DB instance.
Start -> All Programs -> Oracle Database 10g Express Edition -> Start Database

This has been a weird one, finding version information on the operating systems.
On Ubuntu, the following gets the version information
  cat /etc/issue
  cat /etc/lsb-release

On Linux, finding the kernel version
  uname -a
  cat /proc/version

On Windows, from Start-> Run -> cmd.exe
  winver
OR
  systeminfo

This is very simple but still there are a few times when memory fails and we’re not able to do the obvious.

To see the information about the hardware mapping :
  lshal

Finding your CPU Information
  cat /proc/cpuinfo

Finding memory information
  cat /proc/meminfo

Maximum number of SYN requests that the host will remember which did not receive an ACK from clients:
  cat /proc/sys/net/ipv4/tcp_max_syn_backlog

Finding data bus-size or bit-size i.e., whether my CPU is 32-bit or 64-bit:
  sudo lshw -C cpu | grep width

Long time since I posted anything here …. but it’s just been those times been busy as a bee. So securing Cisco routers is a big deal especially since the routers (especially the edge routers) can be critical to any organizations infrastructure. I am not a Cisco guru but am only a student. However, I thought I should create a list that could help me perform security reviews of routers.
Security of routers is important as attackers could add static routes, advertise bad BGP neighbours on edge routers, create inbound tunnel into the intranets and such. Therefore, it’s imperative that adequate efforts be put in to secure Cisco routers.

I thought I’ll put in my first attempt at creating a small checklist:

1. Use SSH for non-console access (“line vty” command should not have telnet in it)
2. Use class 5 passwords, do *not* use class 7 passwords as they’re easily reversed (“enable secret”) alongwith the use of strong passez
3. Limit virtual terminal access by using an ACL
      access-list 100 permit 10.10.10.10 log
      access-list 100 permit 10.10.10.11 log
      access-list deny any log
      line vty 0 4
       access-class 100 in
4. Disable Proxy ARP on each interface (“no ip proxy arp”)
5. Disable CDP as it can be used for information disclosures (“no cdp run”)
6. Use AAA (TACACS+ or RADIUS) (“aaa new-model”, “aaa authentication”, etc.)
7. Use “access-list ACL_NAME deny ip any any log” at the end of each ACL
8. Disable http server (“no ip http server”)
9. Keep the IOS versions updated
10. Set centralized logging using a syslog (“logging internal_ip_address”)
11. Configure NTP to keep the time synchronization (“ntp server 129.6.15.28”)
12. Disable TCP and UDP small services e.g., echo, chargen, discard, etc. (“no service tcp-small-servers” and “no service udp-small-servers”)
13. Put RFC 1918 (ingress filtering) protections using ACLs
       access-list 100 deny ip 127.0.0.0 0.255.255.255 any log
       access-list 100 deny ip 10.0.0.0 0.255.255.255 any log
       access-list 100 deny ip 192.168.0.0 0.0.255.255 any log
       access-list 100 deny ip 172.16.0.0 0.15.255.255 any log
14. Put some more filtering for common IPs
       access-list 100 deny ip 169.254.0.0 0.0.255.255 any log
15. Use SNMPv3 with ACLs if you must (“snmp-server v3 auth priv”)
16. Use SSHv2 (“ip ssh version 2”)
17. Try to use EIGRP instead of RIP/OSPF (“ip authentication mode eigrp N md5”)
18. Use MD5 authentication for RIP/OSPF if you must use these protocols (RIPv2/OSPF)
    (“ip rip authentication mode md5”)
19. For edge routers using BGP authentication (if possible)
       router bgp 10
        neighbor 10.10.10.10 password Cr4zY$%^
20. Configure BGP route flap dampening that prevents BGP oscillations (“bgp dampening”)
21. Use warning banners that could be used for legal purposes for prosecuting hackers