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Recently I upgraded my single “LAMP” setup with two Apache front-ends, and two MySQL mirrored backends. When moving Wordpress to the new web servers I came across an issue with MySQL connections. The /var/log/audit/audit.log shows: type= AVC msg=audit(1401916568.434:533): avc: denied { name_connect } for pid=31254 comm=“httpd” dest=3306 scontext=system_u:system_r:httpd_t:s0 tcontext=system_u:object_r: mysqld_port_t:s0 tclass=tcp_socket type=SYSCALL msg=audit(1401916568.434:533): arch=c000003e syscall=42 success=no exit=-13 a0=10 a1=7fffdda48c20 a2=10 a3=10 items=0 ppid=1685 pid=31254 auid=4294967295 uid=48 gid=48 euid=48 suid=48 fsuid=48 egid=48 sgid=48 fsgid=48 tty=(none) ses=4294967295 comm=“httpd” exe="/usr/sbin/httpd" subj=system_u:system_r:httpd_t:s0 key=(null) ...

If you’re missing the nice little graph and metrics that show in your Task Manager’s Performance tab on Windows 8 and 8.1, but not on 2012 and 2012 R2, all you have to do is run: diskperf -Y Before: After:

For a while now I’ve had a server rack hosting my lab environment, but it’s always been exposed to bad temperature conditions. Since moving to our own house the rack has been sitting in the attached garage, where it gets up to 90F in the summer and as low as 20F in the winter. So far all equipment in the rack survived the abuse, but it was difficult to work on stuff during extreme weather, it meant either freezing or sweating during seasons. And that’s not all, the only electrical circuit that went to the garage also ran the outside lights, kitchen and living room outlets, and would trip at least once a week. ...

If you are using Apache as the reverse proxy for Lync, you may experience some issues when signing in using the mobile app (I only tested iOS). Things to look for are: 50/50 chance in sign-ins (first fails, second works, as shown below) Calls (audio or video) fail to establish Signing out of the application produces an error as shown below To resolve, look for the DefaultType directive in your httpd.conf. If it’s set to text/plain, change it to None and reload Apache config. The line should read: ...

Instead of hunting down Domain Controllers in ADSS and replicating each manually after some last-minute changes, you can run the following repadmin command to run a sync against all the connections: repadmin /syncall /APed The /APed stands for A ll-partitions, P ush, E nterprise-cross-sites and D istinguished names. This will replicate all domain controllers simultaneously.

If you ever want to query AD for Certification Authorities, skip ADSI Edit… there’s a quick way to do it using certutil. Here’s how: certutil -config - -ping Note the extra empty dash between -config and -ping is needed to query the list of CAs. Credit for the useful command goes to colleague and UC ninja Jeff Carlson.

Recently I came across an issue where the Edge server would not replicate the topology. After spending some time looking through firewall ACLs, NAT exemptions, packet captures and the rest of the usual networking stuff, it turns out the problem was WAY more obscure than simple connectivity… If your Edge server’s Trusted Root CA store contains over 100 entries, the SChannel security package will truncate this list internally and depending on where your internal Root CA sits in the alphabetical order, it could be truncated and affect the ability to replicate the Lync topology over HTTPS 4443. ...

Being on Windows 8’s lock screen will automatically turn your display off after 1 minute regardless of your power settings. Even if you have your screen set to never turn off, the lock screen will override that setting and turn off displays after the minute passes. To enable the setting under Display for Advanced Power Options, do the following registry change under HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Power\PowerSettings\7516b95f-f776-4464-8c53-06167f40cc99\8EC4B3A5-6868-48c2-BE75-4F3044BE88A7 Change Attributes from 1 to 2 Open the Advanced Power Options for your profile and you will now see the option. Enjoy! ...

Windows 8 now introduced taskbar options when using multiple displays! You can set it to show all programs, show only those which are active on the display, or just turn the feature off (but WHY would you do that?).

The Dell PERC H200 is a very basic RAID controller that does not have battery-backed cache, and therefore does not let you enable Write Caching within the OS. Writes using the H200 adapter can be very slow, so much that Windows Updates could take 2 to 3 hours on a RAID1! To force enable write cache on an H200 adapter (at your own risk), do the following: