04-11-2007 12:58 AM
I have a server who is accessed by lots of PC's.
Each PC is a DHCP client (lease time 21 days), thus, in most of time, pc's keep their address.
A dns name was attributed to each possible address.
Thus, a pc connects to the server, OpenVMS TCPIP makes a reverse request and obtains the dns name of the pc. Then logicalname "SYS$REM_NODE" and "SYS$REM_NODE_FULLNAME" are defined to dns node name.
Now, network team decides to suppress PC's from the dns and from the reserve table.
Thus a reverse request on a ip address of a pc give an empty respond.
My problem is that the reverse definitions seems to be conserved somewhere in cache on my server because after a new login, logical names are still pointing to old dns name.
Is there a way to flush this cache or must I wait the TTL (I don't know how long it is).
Thanks for your help
Banksys - Belgium
Solved! Go to Solution.
04-11-2007 01:58 AM
resolver's cache, if there is one. (There is
a SYS$SYSTEM:TCPIP$RNDC.EXE, which might be
able to do something with a BIND _server's_
> [...] after a new login [...]
Log in how?
Around here, with Telnet and rsh, my
SYS$REM_NODE and SYS$REM_NODE_FULLNAME both
show an IP address, not a name. With _ssh_,
I see the name for both.
alp $ tcpip show version
HP TCP/IP Services for OpenVMS Alpha Version V5.4 - ECO 6
on a COMPAQ Professional Workstation XP1000 running OpenVMS V7.3-2
(That was all very helpful, right?)
04-11-2007 02:05 AM
I defined my pc address and the name is shown in sys$rem_node. Even 45 min after I deleted the name it is still shown in the logical.
Even re-enabling telnet doesn't clear it.
04-11-2007 02:20 AM
The login is made via terminal emulation reflexion (telnet).
HP TCP/IP Services for OpenVMS Alpha Version V5.4 - ECO 5
on a AlphaServer GS160 6/731 running OpenVMS V7.3-2
04-11-2007 04:20 AM
I think I've read somewhere, that there are no commands in HP OpenVMS TCPIP to flush the DNS name resolver cache.
Did you try disabling and re-enabled the TCPIP BIND resolver ?
$ TCPIP SET NAME/DISABLE/SYSTEM
$ TCPIP SET NAME/ENABLE/SYSTEM
04-11-2007 05:02 AM
I use this whenever people want to rshell, telnet, etc to the machine. It sets up the symbol "remote_node". Thats then used for displaying X or finding the remote machines IP.
(except from one of my command files)
$ remote_node = "''f$trnlnm("sys$rem_node")'"
$ remote_node = f$extract(0,f$locate("::","''remote_node'"),remote
$ if remote_node .eqs. "TELNET" .or. remote_node .eqs. "RSHELL" -
.or. remote_node .eqs. "RLOGIN" .or. remote_node .eqs. "REXEC"
$ remote_node = "''f$trnlnm("sys$rem_id")'"
$ ad1 = %x'f$extract(0,2,remote_node)
$ ad2 = %x'f$extract(2,2,remote_node)
$ ad3 = %x'f$extract(4,2,remote_node)
$ ad4 = %x'f$extract(6,2,remote_node)
$ remote_node = "''ad1'.''ad2'.''ad3'.''ad4'"
04-11-2007 05:13 AM
Existing sessions displayed via logical names will not be updated to reflect changes in rdns.
Being paranoid, I'd probably only try this on a test system first, and not on a production server.