RBLs - more hassle than benefit

as I wrote earlier Google mail servers got blacklisted , but it was only the beginning. Now I got complains from the client that hotmail.com users also get mail bounced because of this list . So, as running after each and every IP blocked by this list endlessly wasn't the best …



Do not miss the long awaited addition to the Fortigate 4 MR2 – sFlow data export

Great news – now Fortigate supports exporting data flows statistics to an external server using sFlow protocol (twin of Netflow from the Cisco world). I configured it in about a minute and it just works. To collect the sFlow data I use nfdump/Nfsen , that I found to be the most …



Darknet can't lie - most of the attacks, scans and other interesting things

indeed come from behind the Great Firewall of China. wordpress_id: 1230 category: Linux tags: awk weekly Working for ISP entitles me to various perks, one of them is unlimited connection to the Internet with wealth of unallocated yet IP addresses. So to use it somehow I set up a little …



Funny things people do - how to turn Checkpoint UTM 450 into Windows Media player

Someone has finally found the best use of the Checkpoint UTM 450 - turned it into the Windows Media player and recorded the instructions so others may follow. In case you still wonder - yes , it certainly voids the warranty. Enjoy youtube.com And to those very few that will try to …



You need no MX record to get mails

That one is funny. One client of ours that is actually themselves provide ISP services in a far-far-away land asked to add PTR record for their mail server . But that was dull, the interesting part was that their domain had absolutely NO MX record ! Only A record for the mail …



Skynet got blacklisted - Google mail servers entered RBL of Sorbs.net

When yesterday my client sent me the headers of blocked by eSafe (Aladdin) mails I was quite surprised - the message said " Google tried to deliver your message, but it was rejected by the recipient domain. We recommend contacting the other email provider for further information about the cause of this …



How come assigning VPN user to specific group takes just one command but no one does it ?

Group locking, as Cisco call it, has been available since ancient IOS 12.2(13)T (circa 2003) and still – most of the set ups I see of clients’ VPN servers at most use different VPN groups for different privilege access requirements and blissfully ignore the fact that all it …



Turn the Checkpoint firewall into network-neutral router and do it in 2 minutes.

It was rather unusual request of the client that for no matter which reasons asked me to “shut down the Checkpoint firewall”. What ? “Shutdown, you know, that it just passes the traffic from interface to interface by its routing table no checking , also I need to add few routes on …



Few questions you will most probably hear on your next job interview.

Lately, for whatever reason it may be, many of my friends/colleagues/acquaintances switched the jobs and mostly because they wanted to. And hearing their accounts of job search I catch myself that while offered positions and employers differ there are ever returning themes/questions that arise on the job …



Number of connected SecureClient or Secureremote users

Here is how to see number of connected to the gateway users. Nothing special/interesting and I am sure somewhere in the SecureKnowledgeBase it is to be found but with recent licensing improvements people ask a lot about that. fw tab -t userc_users -s HOST NAME ID #VALS #PEAK #SLINKS …