when using IP address in target OS map, the DNS lookup looks awful

the synthetic request make hostdb probes twice as it take 127.0.0.1 as hostname in the first probe:

[Dec 19 00:42:24.656] Server

{47412680705808} DEBUG: (hostdb) probe 127.0.0.1 F9D5E018CA21DEE0 1 [ignore_timeout = 0]
[Dec 19 00:42:24.656] Server {47412680705808}

DEBUG: (hostdb) stale 728 1292689815 2097151, using it and refreshing it
[Dec 19 00:42:24.656] Server

{47412680705808} DEBUG: (hostdb) immediate answer for 127.0.0.1
[Dec 19 00:42:24.656] Server {47412680705808}

DEBUG: (hostdb) probe (null) AA30DE0F80A82135 1 [ignore_timeout = 0]
[Dec 19 00:42:24.656] Server

{47412680705808} DEBUG: (hostdb) immediate answer for <addr>
[Dec 19 00:42:24.656] Server {47412680705808}

DEBUG: (hostdb) hostname = localhost

when using IP host as OS in remap, the dns lookup looks awful:

[Dec 19 00:42:34.662] Server

{47412681758480} DEBUG: (hostdb) probe 127.0.0.1 F9D5E018CA21DEE0 1 [ignore_timeout = 0]
[Dec 19 00:42:34.662] Server {47412681758480}

DEBUG: (hostdb) immediate answer for 127.0.0.1
[Dec 19 00:42:34.662] Server

{47412681758480} DEBUG: (hostdb) probe (null) AA30DE0F80A82135 1 [ignore_timeout = 0]
[Dec 19 00:42:34.662] Server {47412681758480}

DEBUG: (hostdb) immediate answer for <addr>
[Dec 19 00:42:34.662] Server

{47412681758480}

DEBUG: (hostdb) hostname = localhost
[Dec 19 00:42:36.294] Server

{47412671220544} DEBUG: (hostdb) probe 115.238.23.250 247FD52B368AF112 0 [ignore_timeout = 0]
[Dec 19 00:42:36.294] Server {47412671220544}

DEBUG: (hostdb) delaying force 0 answer for 115.238.23.250 [timeout 0]
[Dec 19 00:42:36.310] Server

{47412671220544} DEBUG: (hostdb) probe 115.238.23.250 247FD52B368AF112 0 [ignore_timeout = 0]
[Dec 19 00:42:36.310] Server {47412671220544}

DEBUG: (hostdb) DNS 115.238.23.250
[Dec 19 00:42:36.310] Server

{47412671220544} DEBUG: (hostdb_insert) inserting in bucket 620
[Dec 19 00:42:36.310] Server {47412671220544}

DEBUG: (hostdb) inserting for: 115.238.23.250: (md5: 247FD52B368AF112) now: 1292690555 timeout: 2097151 ttl: 2097151
[Dec 19 00:42:36.310] Server

{47412671220544} DEBUG: (hostdb) done 115.238.23.250 TTL 2097151
[Dec 19 00:42:36.310] Server {47412671220544}

DEBUG: (hostdb) probe (null) 3566BAF8CDEE083D 0 [ignore_timeout = 0]
[Dec 19 00:42:36.310] Server

{47412671220544} DEBUG: (hostdb) delaying force 0 answer for (null)
[Dec 19 00:42:36.310] Server {47412671220544}

DEBUG: (hostdb) probe 3566BAF8CDEE083D 0 [ignore_timeout = 0]
[Dec 19 00:42:36.310] Server

{47412671220544} DEBUG: (hostdb) DNS IP 115.238.23.250
[Dec 19 00:42:36.310] Server {47412671220544}

DEBUG: (dns) received query s�� type = 12, timeout = 0
[Dec 19 00:42:36.312] Server

{47412671220544} DEBUG: (dns) enqueing query 250.23.238.115.in-addr.arpa
[Dec 19 00:42:36.312] Server {47412671220544}

DEBUG: (dns) adding first to collapsing queue
[Dec 19 00:42:36.312] Server

{47412671220544} DEBUG: (dns) send query for 250.23.238.115.in-addr.arpa to fd 33
[Dec 19 00:42:36.312] Server {47412671220544}

DEBUG: (dns) sent qname = 250.23.238.115.in-addr.arpa, id = 21309, nameserver = 0
[Dec 19 00:42:36.312] Server

{47412671220544} DEBUG: (dns) sent_one: failover_number for resolver 0 is 1
[Dec 19 00:42:36.350] Server {47412671220544}

DEBUG: (dns) received packet size = 103
[Dec 19 00:42:36.350] Server

{47412671220544} DEBUG: (dns) primary DNS response code = 3
[Dec 19 00:42:36.350] Server {47412671220544}

DEBUG: (dns) received rcode = 3
[Dec 19 00:42:36.350] Server

{47412671220544} DEBUG: (dns) DNS error 3 for [250.23.238.115.in-addr.arpa]
[Dec 19 00:42:36.350] Server {47412671220544}

DEBUG: (dns) domain extending 250.23.238.115.in-addr.arpa
[Dec 19 00:42:36.350] Server

{47412671220544} DEBUG: (dns) new name = . retries = 5
[Dec 19 00:42:36.350] Server {47412671220544}

DEBUG: (dns) send query for . to fd 33
[Dec 19 00:42:36.350] Server

{47412671220544} DEBUG: (dns) sent qname = ., id = 30807, nameserver = 0
[Dec 19 00:42:36.350] Server {47412671220544}

DEBUG: (dns) sent_one: failover_number for resolver 0 is 1
[Dec 19 00:42:36.701] Server

{47412671220544} DEBUG: (dns) received packet size = 92
[Dec 19 00:42:36.701] Server {47412671220544}

DEBUG: (dns) primary DNS response code = 0
[Dec 19 00:42:36.701] Server

{47412671220544} DEBUG: (dns) received rcode = 0
[Dec 19 00:42:36.701] Server {47412671220544}

DEBUG: (dns) DNS error 0 for [.]
[Dec 19 00:42:36.701] Server

{47412671220544} DEBUG: (dns) FAIL result for . = <not found> retry 0
[Dec 19 00:42:36.701] Server {47412671220544}

DEBUG: (dns) called back continuation for .
[Dec 19 00:42:36.701] Server

{47412671220544} DEBUG: (hostdb) probe 3566BAF8CDEE083D 0 [ignore_timeout = 1]
[Dec 19 00:42:36.701] Server {47412671220544}

DEBUG: (hostdb) failed for 115.238.23.250
[Dec 19 00:42:36.701] Server

{47412671220544} DEBUG: (hostdb_insert) inserting in bucket 2221
[Dec 19 00:42:36.701] Server {47412671220544}

DEBUG: (hostdb) inserting for: : (md5: 3566BAF8CDEE083D) now: 1292690555 timeout: 0 ttl: 0
[Dec 19 00:42:36.759] Server

{47412671220544} DEBUG: (hostdb) probe 115.238.23.250 247FD52B368AF112 1 [ignore_timeout = 0]
[Dec 19 00:42:36.759] Server {47412671220544}

DEBUG: (hostdb) immediate setby for 115.238.23.250
[Dec 19 00:42:44.664] Server

{47412679653136} DEBUG: (hostdb) probe 127.0.0.1 F9D5E018CA21DEE0 1 [ignore_timeout = 0]
[Dec 19 00:42:44.664] Server {47412679653136}

DEBUG: (hostdb) immediate answer for 127.0.0.1
[Dec 19 00:42:44.665] Server

{47412679653136} DEBUG: (hostdb) probe (null) AA30DE0F80A82135 1 [ignore_timeout = 0]
[Dec 19 00:42:44.665] Server {47412679653136}

DEBUG: (hostdb) immediate answer for <addr>
[Dec 19 00:42:44.665] Server

{47412679653136}

DEBUG: (hostdb) hostname = localhost

we should fix it in http or hostdb