Changing the Postfix maximum email size

I've recently had some of my customers emailing me large image attachments and my Postfix mail server has been rejecting them. A quick look at the postfix configuration showed the message size limit was the default so I needed to increase it. This post looks at how to see what the current email message size limit is with Postfix and how to change it.
The configuration option is "message_size_limit" and by default is set to 10240000 bytes which is roughly 10MB. You can see what setting your postfix install is currently using by issuing the following command:

postconf | grep message_size_limit

Just doing "postconf" on its own will show all the options so using grep on "message_size_limit" filters the output to just the setting we want. For the default setting, you'll see this:

message_size_limit = 10240000

To change the setting to some other value, open the main.cf file in your favourite text editor (it's often at a location like /etc/postfix/main.cf) and either edit or add the following line, depending if it's already in the file or not.

message_size_limit = 20480000

In the above example I've changed it to ~20MB.
Then reload postfix like so:

service postfix reload

and your setting will take effect. You can query postconf again if you want to check all is as expected.

Troubleshooting the vCenter Server Appliance with Single Sign-On login (2033338)

Details

• The two most common network-related problems when connecting to a vCenter Server Appliance using the Web Client and Single Sign-On (SSO) are SSL certificate failure and a changed SSO server IP address.
• You see these errors:
  
• Failed to connect to VMware Lookup Servicehttps://vCVA_IP_address:7444/lookupservice/sdk - SSL certificate verification failed.
• Failed to communicate with the vCenter Single Sign On server https://vCVA_IP_address:7444/ims/STSService.

Solution

If the SSO SSL certificate failed, the network identification for the vCenter Server Appliance has changed, but the SSO SSL certificate has not been updated to match it. For instructions on changing the certificate,

Note: These issues affect the Web Client and other related services running within the vCenter Server Appliance. These steps involve logging into the vCenter Server Appliance Management Interface (VAMI) which should not be affected.

To resolve this issue, toggle the certificate settings.

To toggle the certificate settings:

1. Log in to the vCenter Server Appliance Web interface at https://hostname:5480/.
2. Click the Admin tab.
3. Regenerate certificates:
   
   • vCenter Server 5.1: Select Toggle certificate setting so that the Certificate regeneration enabled displays Yes.
   • vCenter Server 5.5: Select Yes under Certificate regeneration enabled.
     
4. Click Submit.
5. Restart the vCenter Server Appliance.
6. After the vCenter Server Appliance restarts, confirm that the Certificate regeneration enabled option is set to disabled.

Notes:

• vCenter Server generates new default certificates using this option. For systems that use custom certificates, regenerate the certificates manually.
• Regeneration of default certificates takes longer time to complete.

Checksum on Solaris OS

Here i share how to checksum file or folder on Solaris OS :
  on file

$ sum  <filename>

$sum ABC.dmp
21882 7592 ABC.dmp

 on folder

tar cf - <directory name> | sum -