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Monday, November 10, 2014

Ifconfig: command not found

CentOS, say it isn't so! Having just done the minimal install of CentOS 7 as a VM, I wanted to install VMware tools. I thought I installed all the prerequisites when the script halted at "Setup is unable to find the "ifconfig" program on your machine."

I ended the script and incredulously ran the ifconfig command, thinking it had to be wrong, but it's no longer included. The ip command has now taken over networking duties, but the VMware script didn't care. I ran yum provides ipconfig, but no love: "No package ifconfig available". A couple of web searches later and I found the package I needed to bring it back...

# yum install net-tools

BTW, don't be surprised if Fedora and RHEL (and it's other offspring) are missing ifconfig as well.

Sunday, November 2, 2014

Developer Cannot Be Confirmed

I bought a new camera recently and decided I needed the "old" version of Photoshop I had lying around on my MacBook so I could salvage pics taken with my n00btastic photo skills. So as any reasonable person would do, I installed and then attempted to update Photoshop with the latest available patch from Adobe.

Finding the correct patch on Adobe's site wasn't exactly intuitive, which is surprising from a company that specializes in making software for the web, anyway I digress. Once the patch was downloaded, it wouldn't install. "AdobePhotoshop12-4-mul-AdobeUpdate.dmg can't be opened because the identity of the developer cannot be confirmed." Seems hard to believe, and I'm not sure who's to blame here, but after some searching it seems there are a number of rather large companies, i.e. Oracle, that have the same issue. (Either devs are signing their apps incorrectly or Apple released a patch/update breaking the previous verification mechanism.)

In any case, if you trust the developer, this can be overruled with a few clicks and your password:

System Preferences > Security & Privacy > General tab and you will see "App in question" was blocked from opening because the identity of the developer cannot be confirmed.

Click the button to allow anyway and enter your password, the app should start installing immediately.

Wednesday, October 8, 2014

Disabling the Yum RHN Plugin

Due to the sheer number of RHEL installs we have on our network it was time to have our own Yum repo. The setup was fairly straightforward and their are many useful articles available.

Once setup and configured, testing began; both the new test systems worked perfectly. But apparently it was too soon to start slapping myself on the back, because systems already registered with RHN would error out once I removed their subscription, rather than use the local repo.

"There was an error communicating with RHN.
RHN Satellite or RHN Classic support will be disabled.
Error communicating with server. The message was:

Error Message:
        Please run rhn_register as root on this client
Error Class Code: 9
Error Class Info: Invalid System Credentials.
"

I did many an Internet search only to find numerous suggestions that didn't fix the problem. It wasn't until I looked at the man page for yum.conf did I see the answer. The related files portion at the bottom listed a number of other files, the important one under /etc/yum/pluginconf.d the rhnplugin.conf file. Setting it to enabled=0 stops the plugin from being used and voilĂ , the local repo was working. With each of these, I also follow up with a yum clean all just to be sure it's a fresh start.

Sunday, March 31, 2013

Excel Closing Slowly

Excel seemed to open fast enough for someone in our accounting department, but its closing was glacial.

I removed all Add-ins (File > Options > Add-Ins) and even started it in Safe Mode (Run... excel /s), but it still lagged on close.

Not surprising, Excel has a default template like Word's Normal.dot named ExcelXX.xlb, XX being the version number of Excel, in this case it's 2010 which is version 12.

Once Excel12.xlb was renamed in C:\Users\%username%\AppData\Roaming\Microsoft\Excel, the file was regenerated upon start starting Excel and from then on, it closed without hesitation.

For further troubleshooting steps, visit the overlords at Microsoft.

Friday, February 22, 2013

Changing the Default Windows Icon

I don't know about you, but always having the "orange flower" icon whenever I log into a new account on a system or use the Remote Desktop client has gotten old.

Of course, you can change the account icon by clicking on it from the Start Menu, bringing you into Control Panel > User Accounts to select Change your picture and choose from the list available or Browse for more pictures...

But if you want to change the default permanently, grab yourself a 128 x 128 bitmap (.bmp) image and name it user.bmp and dump it into: C:\ProgramData\Microsoft\User Account Pictures, confirm to overwrite.

You can also add your own icons to the list offered by naming the bitmaps usertile45.bmp, usertile46.bmp, etc. and placing them in: C:\ProgramData\Microsoft\User Account Pictures\Default Pictures

As you would imagine, this works for Windows Vista and 2008/R2. Still don't have a Windows 8 system to use, so you're mileage may vary with that...

Wednesday, December 26, 2012

Testing an External NTP Server

First off, NTP uses port 123. That was the first thing I checked when trying to telnet to one of the pool.ntp.org servers. Seems most NTP server ignore the telnet command.

Then I thought I'd use net time, but it has been deprecated in Windows 7 in favor of the newer w32tm command.

There's a litany of switches to use with it, but the /monitor /computers:server are the ones you want.

And using the command: c:\w32tm /monitor /computers:time.nist.gov
You will get the following output, showing it works:

time.nist.gov[64.250.177.145:123]:
    ICMP: 59ms delay
    NTP: -0.1402919s offset from local clock
        RefID: 'ACTS' [0x53544341]
        Stratum: 1

You can find a huge amount of popular public NTP servers at NTP.org

Monday, November 19, 2012

Finding a Linux Application Version

During a recent Wordpress installation endeavor, I needed to confirm I had the correct versions of Apache, PHP, etc., and didn't exactly know how to accomplish that. As with many things in the computer world, there are many ways to skin a cat...

This example uses Apache, which is httpd as a service (daemon in Linux-speak).

Add -v to the binary (or -V depending on the app), and this doesn't work for everything.
[root@spidey ~]# httpd -v
Server version: Apache/2.2.15 (Unix)
Server built:   Feb  7 2012 09:50:11

Use which to locate the full path of a command
[root@spidey ~]# which httpd
/usr/sbin/httpd

Use whereis to locate the binary, source and man pages
[root@spidey ~]# whereis httpd
httpd: /usr/sbin/httpd /usr/sbin/httpd.event /usr/sbin/httpd.worker /etc/httpd /usr/lib64/httpd /usr/share/man/man8/httpd.8.gz

Querying the installed package by using rpm -q
[root@spidey ~]# rpm -q httpd
httpd-2.2.15-15.el6_2.1.x86_64

You can do a locate to see everywhere on the system httpd shows up
[root@spidey ~]# locate httpd
/etc/httpd
/etc/httpd/conf
/etc/httpd/conf.d
/etc/httpd/logs
...

Or a find with -name

[root@spidey ~]# find / -name httpd
/etc/httpd
/etc/rc.d/init.d/httpd
/etc/sysconfig/httpd
/etc/logrotate.d/httpd
...

And yes, I did have the correct version :)