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If you're using a non-standard MySQL data directory on your Red Hat Enterprise Linux (RHEL) server, you may have seen an error like /usr/libexec/mysqld: Can't change dir to '/mysql_data/' (Errcode: 13). The key to fixing this problem is to ensure the new MySQL data directory has the proper …
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During his keynote speech at Oracle OpenWorld, Larry Ellison announced the launch of the Exalogic Elastic Compute Cloud. This appliance includes 30 Sun servers with 360 processor cores, 2.8 TB RAM, and a built-in storage unit capable of 40 GB/sec.
Bundled software includes:
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While doing some testing with Cisco Access Registrar (CAR) 5.0, I noticed that the test user had hundreds of old sessions hanging around:
--> query-sessions /r with-User X
Sessions with-User X for /Radius
Sessions for /Radius/SessionManagers/session-mgr-1:
S432 Key: 04000000000CF660, NAS: NAS.slaptijack.com, NAS-Port: 0, User-Name: X, Time …Posted on in System Administration
Users of Citrix XenServer 5.6 are experiencing a problem where the cdrommon process begins consuming all CPU resources and affecting virtual machine performance. Using 'top' or 'ps auwx' from dom0 shows that the process is consuming 99% or more CPU resources. Users of Xen Cloud Platform (XCP) 0.5 …
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We ran across the following error on a MySQL slave server recent:
mysql> SHOW SLAVE STATUS \G
<snip>
Last_Error: Query caused different errors on master and slave. Error on master: 'Deadlock found when trying to get lock; try restarting transaction' (1213), Error on slave: 'no error' (0). Default database: '<database_name …Posted on in System Administration
Daniel Feller, Lead Architect at Citrix Systems, recently concluded a series of blog posts highlighting the top ten desktop virtualization mistakes made by implementers. Here is a summary of the mistakes and links to Daniel's blog.
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As every system administrator is aware, keeping precise time on your servers can be critical. For example, if you use QueueMetrics for your Asterisk-based call center and the QM and MySQL servers are running with different times, users will notice confusing behavior as calls seem to arrive in the future …
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On one of the WordPress-based websites I maintain, I have removed the category base so that, when browsing a category the url doesn't end with /category/category-slug/. I accomplished that by putting a single '.' in the "Category base" text box of the Permalinks admin page. This worked fine until I …
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While setting up a new blog for an old site the other day, I ran into a situation where the main page would work, but individual posts would result in a 404 (page not found) error. Checking the error log revealed that Apache could not find the file it was …
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Configuring your syslog server to accept logging output from your Cisco routers and switches requires a few basic steps. We'll assume that you are using a new server and haven't made any previous changes to the syslog configuration. I use <acronym title="Red Hat Enterprise Linux">RHEL</acronym> 5 most …
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