Anti-virus / Anti-SPAM, Mail relaying
Barracuda User Creation
I have a customer running a Barracuda SPAM firewall 300. The customer has the specific request that only the administrator can look at Quarantine messages and users shouldn’t get their own Quarantine inbox. To accomplish this I have configured the Quarantine Type: Global. I see that all Quarantine messages are delivered in the globally configured … Read More
relays.ordb.org
Since the day before yesterday, some of our customers complained having problems with receiving e-mail. The senders from the e-mail noticed that their mail had been blocked by relays.ordb.org. This RBL is offline, according to this article, at least everybody thought. Seems to me, the RBL came online yesterday and blocked everything. I have heard … Read More
ProCurve excessive STP topology changes
Recently a colleque of mine noticed something strange in the STP configuration from a couple of HP ProCurve switches. He had a network, which was configured by another party, with switches running MST en RSTP mode spanning-tree. He noticed a lot of topology changes in the configuration, but couldn’t find out where they were coming … Read More
NTP Configuration
The right time synchronization is very important while troubleshooting different kind of problems. Most network components have the option to synchronize their time with a time server on the internal network or the internet. This post shows how to configure NTP with the right time zone on Cisco and HP ProCurve components. The example configurations … Read More
HP ProCurve licenses
During an check-up on a network, I looked at the configuration of two HP ProCurve 5400zl switches. One of these switches functions as the core switch and default gateway for the various VLANs. To improve the availability and redundancy of the default gateway, I mentioned the configuration of VRRP (Virtual Router Redundancy Protocol). On of … Read More
Cisco Networkers 2008
Cisco Live (aka Cisco Networkers) 2008 has opened the registration for Orlando, Florida. Cisco Live is Cisco’s annual IT and communications conference. The conference features Networkers, the premier education and training program, and other special programs designed to meet the diverse needs of today’s IT and communications professional from increasing technical proficiency to understanding the … Read More