I faced a problem when the dns name and also ip address of the sybase source database changed.
According to the instruction I changed parameter HOST as
avsybdb alter_source -srcname sybase1 HOST=newhost
and it was succesfully changed, but ip address of the source remains the same as for old hostname,
avsybdb alter_source -srcname sybase1 HOSTIP=newhostip
exits with error - unknown parameter HOSTIP.
Is the only way to change ip address is to drop source and to add new one?
Please check the documentation for the avsybdb alter_source command.
There you will find that you can change the source IP address using the [attrname=attrvalue] syntax, and specifically, the keyword HOSTIP, as you used it, should actually be HOST_IP with the underscore.
The error message was trying to tell you to go look up the correct syntax.
Please take a look at the Administrator's Guide, chapter 10 - http://download.oracle.com/docs/cd/E14472_01/doc.102/e14459/avadm_app_avsybdb_ref.htm#BABJEIJF. The way to change the IP address of the source is 'avsybdb alter_source -srcname <source name> HOST_IP=<new IP address>'.
I would really recommend that you upgrade to 10.2.3 Patch Set 2 (version 10.2.3.2.0), if you've not already done so. In addition, please make it a point to stay on the latest bundle patch for Audit Vault (currently at Bundle Patch 2 - bug 9958865). If your issue has not been addressed by one of these patches, and since the product is not behaving as documented, please log an SR with Oracle Support.