|
Problem IC81752
|
Status: Closed |
JCC Driver connection slow due to JDK getHostName() and getCanon icalHostName() when NOT registed the IP ADDRESS in a DNS. |
| product: |
DB2 FOR LUW / DB2FORLUW / 950 - DB2 |
| Problem description: |
The following environment, getConnection may slow performance.
DB2 server host information is NOT existed in /etc/hosts of DB2
Client.
DB2 Client host can lookup DNS host and DNS does not have an
entry of
DB2 server.
ie)
DB2 server host IP address is 192.168.107.155.
# ping 192.168.107.155
192.168.107.155 is alive
NOT existed in /etc/hosts
# grep -c 192.168.107.155 /etc/hosts
0
DB2 Client host can lookup DNS.
# nslookup samplehost
Server: 192.168.107.2
Address: 192.168.107.2#53
Non-authoritative answer:
Name:
Address: 192.168.107.200
DNS does not have an entry of DB2 server.
# nslookup 192.168.107.155
Server: 192.168.107.2
Address: 192.168.107.2#53
** server can't find 155.107.168.192.in-addr.arpa: NXDOMAIN
In this case, getConnection may be slow responce, because DNS
does not have reverse lookup record.
We use getHostName() to get ip address from hostname.
In JDK 1.4.2, changed getHostname behavior as below.
If this InetAddress was created with a host name, this
host name will be remembered and returned; otherwise, a reverse
name lookup will be performed and the result will be returned
based on the system configured name lookup service. |
| Problem Summary: |
First fixed in JDBC driver from DB2 9.7 Fix Pack 7 (JCC driver
version 3.64.106) |
| Local Fix: |
Add entry in your DNS or /etc/hosts. |
| available fix packs: |
DB2 Version 9.7 Fix Pack 6 for Linux, UNIX, and Windows
DB2 Version 9.7 Fix Pack 7 for Linux, UNIX, and Windows
DB2 Version 9.7 Fix Pack 8 for Linux, UNIX, and Windows
DB2 Version 9.7 Fix Pack 9 for Linux, UNIX, and Windows
DB2 Version 9.7 Fix Pack 9a for Linux, UNIX, and Windows
DB2 Version 9.7 Fix Pack 10 for Linux, UNIX, and Windows
|
| Solution |
Upgrade to JDBC driver from DB2 9.7 Fix Pack 7 (JCC driver
version 3.64.106) or higher |
| Workaround |
not known / see Local fix |
| Timestamps |
Date - problem reported :
Date - problem closed :
Date - last modified :
| 01.03.2012
19.05.2017
19.05.2017 |
| Problem solved at the following versions (IBM BugInfos) |
9.7.FP7
|
| Problem solved according to the fixlist(s) of the following version(s) |
| 9.7.0.6
|
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