AI-enabled developer productivity, build systems, and engineering leadership
Posted on in Networking
I saw this error message on a Cisco ASA 5540 today:
%ASA-3-210005: LU allocate connection failed
According to Cisco, this error means the standby unit was not able to create a new connection for stateful failover. The recommendation is to verify that the system has enough RAM.
OK...
# show memory …Posted on in Programming
Chance asked me to post the Perl script I've been using to collect and graph protocol specific usage information in MRTG. Below, you will find a link to the zip file containing the Perl script.
You can put this script where you like, but you will need to reference it …
Posted on in Networking
A buddy of mine is getting about 1 Mbps through his Cisco 2621XM based VPN.
Additionally, the CPU was maxed out during the transfer. (In my testing, I was
able to max out a 7 Mbps cable modem using the
Cisco VPN Client connected
to the same endpoint, so the …
Posted on in voice
You might run into a situation where you have multiple PRIs or T1s for outbound calling on your Cisco Access Server (Cisco AS5350 or other model). In order to ensure that all outbound calls are using both circuits, you need to configure two outbound dial peers. In order for the …
Posted on in Networking
Preserve Cisco router DHCP leases across a reboot by configuring a DHCP database agent, verifying successful writes, and choosing a storage target that fits the platform.
Posted on in Networking
Last week I mentioned that I was working on a Quality of Service (QoS) project. For those who are curious about QoS and how to get it working, here are the resources I found most useful. These resources are mostly Cisco specific, but the principles should be applicable in many …
Posted on in Networking
I decided I needed a standardized set of Quality of Service classification access-lists for some work I'm doing. Check out my Cisco QoS Classification ACLs page and let me know what you think.
If you have any ideas on how I can improve the lists, leave a comment here or …
Posted on in Networking
This week I tried upgrading a Cisco Catalyst 2960 to the newest software release — 12.2(46)SE. The upgrade went just fine, but I noticed that the monitoring software was throwing SNMP errors.
In case you don't know much about SNMP, an ifIndex identifies a specific interface on a …
Posted on in networking
I've been working on a standardized list of access lists to use in conjunction with QoS on Cisco routers and switches. I've tried to adhere as closely as possible to the Cisco QOS Baseline (pdf).
As I refine the ACLs, I'll keep this page up to date. If you have …
Posted on in Networking
I recently had the pleasure of working on a client's Cisco 2600 series router that had not been used in quite some time. Access lists on the vty lines and a misconfigured con line meant I was locked out. In a situation like this, the only way to gain access …
Posted on in Networking
As you might recall, I had previously taken umbrage with Cisco's inability to forward a range of ports to a particular host. Many readers have offered suggestions and links to other documents around the Internet offering various solutions, but none of them really sat quite right with me.
In hindsight …
Posted on in Networking
Error: The image in the archive which would be used to upgrade
Error: system number 1 does not support the same feature set.
I just got this error message while upgrading a Cisco Catalyst 3560 from 12.2(35)SE5 to 12.2(44)SE. The older version was IP …
Posted on in Networking
Oops! I guess I'm way behind the times.
For quite a while, I've been using ip verify unicast reverse-path to prevent packets with spoofed source addresses from crossing my routers. Apparently, as of IOS 12.0 (12.4 is current as of this writing), that command has been replaced with …
Posted on in Networking
"How do I find a Cisco serial number remotely through the command line?"
This is one of those frequently asked questions that I see over and over. So, here's the quick and dirty answer:
You can find Cisco serial numbers from the IOS command line by using the
show inventory …
Posted on in voice
Note: This is part of a discussion regarding the configuration of a Cisco AS5300 for T.37 Store and Forward Faxing.
The final piece of the T.37 Store and Forward Fax configuration is the dial peers to handle the incoming fax and the outgoing email. I'll walk you through …
