Exchange – Certificate Invalid ‘Revocation Check Failed’
KB ID 0001121 Problem When you check the status of a certificate in Exchange and it it displayed at ‘Invalid’ and the details show that the revocation check has failed. Solution This can happen if your certificate CA has its CRL or OCSP information setup incorrectly, or the Exchange sever simply cannot access them to verify the validity of the certificate. If you are using your own CA the correct way to fix the problem is...
Windows Server 2012 – Add Role Error 0x800f0902
KB ID 0001120 Problem I was setting up a print server yesterday, when I tried to add the print server role it failed with this error; Unable to obtain feature list error 0x800f0902 Solution Internet searching was pointing to a problem with the ‘Task Scheduler Service’ and suggested stopping that, which I was unable to do. It turns out my server had just finished Windows updates, and needed to reboot, (it was a new...
Windows Server 2012 R2 – Stop IE Opening ‘In Metro’
KB ID 0001119 Problem I was working on some Server 2012 R2 servers this morning, and every time I tried to launch IE, instead of the normal IE 11, it stubbornly kept opening the the IE App. Solution Hit the Windows key > Type in ‘internet options’ > make the following changes; Programs Tab > Opening Internet Explorer > Select ‘Always in Internet Explorer on the desktop’ > Apply > OK. Related...
Cisco ASA – Active / Active Failover
KB ID 0001114 Usually when I’m asked to setup Active/Active I cringe, not because its difficult, its simply because people assume active/active is better than active/standby. I hear comments like ‘we have paid for both firewalls lets use them’, or ‘I want to sweat both assets’. The only real practical use cases I can think of for Active /Active are; You have a multi-tenancy environment and want to offer...
Cisco IOS – Setting Up DHCP Scopes
KB ID 0001112 I usually only have to do this on very small sites, or occasionally on the test bench. Most of the time we will have a server sat doing DHCP. The procedure below was carried out on a router, but the procedure is the same for a catalyst switch. By default DHCP is disabled, you have to turn it on, then create a ‘dhcp pool.’ Petes-Router(config)#service dhcp Petes-Router(config)#ip dhcp pool DATA-VLAN-10 Then...