omshell: querying host info via ip address

[Jeff Waller]

Well this is from version 4.2 but I doubt things have changed much, this is the
server source that finds a host entry based on the ip address.

==========
 status = omapi_get_value_str (ref, id, "ip-address", &tv);
        if (status == ISC_R_SUCCESS) {
                struct lease *l;

                /* first find the lease for this ip address */
                l = (struct lease *)0;
                lease_ip_hash_lookup(&l, lease_ip_addr_hash,
                                     tv->value->u.buffer.value,
                                     tv->value->u.buffer.len, MDL);
                omapi_value_dereference (&tv, MDL);

                if (!l && !*lp)
                        return ISC_R_NOTFOUND;

                if (l) {
                        /* now use that to get a host */
                       host = (struct host_decl *)0;
                        host_hash_lookup (&host, host_hw_addr_hash,
                                          l -> hardware_addr.hbuf,
                                          l -> hardware_addr.hlen, MDL);
==========


Apparently, the lease is used to find sufficient information (the mac address)
to find the host, but I wonder, if that host has not made a request yet, will there
be a lease?  As an experiment, could you have that host acquire an IP and then
make the query.  Not sure how to fix yet as there is no host_ip_hash.

-Jeff


On Mar 4, 2012, at 9:45 AM, Will Green wrote:

> Hello,
> 
> I'm trying to manage DHCP entries with omshell, but have hit a
> problem. I am using CentOS 6.2 with isc-dhcpd-4.1.1-P1.
> 
> My leases file contains one entry:
> 
> host foo {
>  dynamic;
>  hardware ethernet 08:00:27:2b:fc:e1;
>  fixed-address 172.16.1.99;
> }
> 
> When I try to query the server about host records I can only find the
> host by name or hardware-address, attempts to look it up via IP
> address fail. What am I missing? omshell output below shows what
> happens:
> 
> $ omshell
>> key (hidden in email)
>> connect
> obj: <null>
>> new host
> obj: host
>> set name = "foo"
> obj: host
> name = "foo"
>> open
> obj: host
> name = "foo"
> ip-address = ac:10:01:63
> hardware-address = 08:00:27:2b:fc:e1
> hardware-type = 00:00:00:01
>> close
> obj: <null>
>> new host
> obj: host
>> set hardware-address = 08:00:27:2b:fc:e1
> obj: host
> hardware-address = 08:00:27:2b:fc:e1
>> open
> obj: host
> hardware-address = 08:00:27:2b:fc:e1
> ip-address = ac:10:01:63
> name = "foo"
> hardware-type = 00:00:00:01
>> close
> obj: <null>
>> new host
> obj: host
>> set ip-address = 172.16.1.99
> obj: host
> ip-address = ac:10:01:63
>> open
> can't open object: not found
> obj: host
> ip-address = ac:10:01:63
> 
> TIA,
> Will
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