On (07/15/09 00:01), Peter Memishian wrote:
> 
>  > So does the following
>  >  ipadm create-addr -i <intf> [-a laddr[,raddr]] <label>
>  > offer potential for confusion? 
>  > (an address pair will be needed for tunnels. <label> will be
>  > used to generate the local address, when no -a arg is supplied)
> 
> So the proposal is to use the label to do a hostname lookup and attempt to
> derive the address from that?  Doesn't that only further the strange
> duality between labels and hostnames?  That is, when the admin first does
> a create-addr, the label doubles as a hostname in that it is looked up to
> determine an IP address.  However, after that point the label is just
> treated as a label, and even if the hostname is changed to refer to a
> different IP address, the label (with the same name as the hostname)
> continues to refer to the old address -- until a delete-addr is done and
> another create-addr is done with the label, in which case it then gets the
> latest address.  Or have I misunderstood what you're proposing?

yes - I have to divorce the hostname-label linkage after the create
to retain predictability (i.e., so that set-addrprop/delete-addr etc
don't go and operate on the wrong address).

For example, let's say someone did

# vi /etc/hosts # setup an entry for myhost
# ipadm create-addr ... myhost

some time later, the admin decides to renumber myhost. so they edit
/etc/hosts again. Now the expected behavior for a command like 
set-addrprop would be to operate on the old ipaddress (if it tried
to operate on the new address it would be forced to return 
"not available"). 

Which is why I first suggested having separate args like 
"-a myhost <label>", so that it's clear that the target of the
addr commands is different from the string used to consult the
resolver. 

BTW, one thing that Vasumathi pointed out: in the proposal 

  ipadm create-addr -i <intf> [-a laddr[,raddr]] <label>

the label has to start with an alphabet (i.e, it can't be
10.1.2.3/24, or we'd fall into the "is the mask needed for
the other commands" rut).

--Sowmini


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