Posted on in System Administration
When I upgraded to OS X 10.7 (Lion), I started using the built-in IPSec VPN client rather than Cisco's VPNClient. I experienced problems immediately. At first it appeared that the connection was being made, but no traffic was passing. When I tried pinging by IP address, I found that …
Posted on in system_administration
If you're a frequent user of GNU screen on your Mac, you are probably tired of
using ctrl-a [ to enter scrollback mode. Adding the following lines to the
.screenrc configuration file in your home directory in order to scroll with
your mouse:
defscrollback 5000
termcapinfo xterm* ti@:te@
Posted on in System Administration
I've dealt with a few servers that have long lived popper (POP3) processes. These processes should be closed once the connection is closed, but they occasionally hang around. Once they get in this state, they will never close on their own. After a while, hundreds of these processes will just …
Posted on in System Administration
One of the beauties of using a Linux-based Mail Transport Agent (MTA) like Sendmail is the ability to pipe mail into programs. You can use this in conjunction with a filtering application like procmail, with a custom application that collects data about the email, or anything else you can imagine …
Posted on in System Administration
Why is it always a pain to find this stuff in the documentation?
Username: admin
Password: ironport
Posted on in System Administration
I use snmptrapd to catch SNMP traps and then put them into a MySQL database using a pretty generic trap handler. This gives me the opportunity to generate such useful information as:
> SELECT HOUR(time) AS "hour", COUNT(*) AS "bounces" FROM snmptraps
WHERE hostname = 'XXX' AND time > '2011-07-25'
AND trap_oid …Posted on in System Administration
Historically, the RPMforge repository has aimed to create add-on RPMs for RHEL, CentOS, and Scientific Linux. Although their goal was not to replace base packages, avoiding that has not always been possible. In mid-November 2010, RPMforge created the rpmforge-extras and moved all packages that replaced base packages into the repository …
Posted on in System Administration
Posted on in System Administration
In the past, I've written about the usefulness of
using iptables to limit incoming SSH connections.
Although it isn't a replacement for a good password policy, it at least limits
the ability of outsiders to perform a brute-force password attack on your system.
Now that I've started using Ubuntu more …
Posted on in System Administration
