If you’ve extended your RAC cluster on a set of new nodes you already know how painful it can be to have to go through the list of your clients and make sure their SQL*Net configuration is up to date. 11gR2 solves this problem using Single Client Access Name (SCAN).
The single client access name (SCAN) is a hostname used to provide service access for clients to the cluster. Because the SCAN is associated with the cluster as a whole, rather than to a particular node, the SCAN makes it possible to add or remove nodes from the cluster without needing to reconfigure clients. It also adds location independence for the databases, so that client configuration does not have to depend on which nodes are running a particular database. Clients can continue to access the cluster in the same way as with previous releases, but Oracle recommends that clients accessing the cluster use the SCAN.
Reference: 1.3.2.2 IP Address Requirements
How is SCAN implemented?
For high availability purposes the SCAN name should be associated with at least three IP addresses using DNS round-robin resolution. If you opt to use Grid Naming Service then GNS can also be used to manage the SCAN name.
SCAN is configured at a cluster level not at the node level, that’s what makes it so flexible — no mater how many nodes your clusters consists of, your clients can continue to use SCAN to access the services of your cluster utilizing all nodes even if you add or delete them:
The SCAN is a virtual IP name, similar to the names used for virtual IP addresses, such as node1-vip. However, unlike a virtual IP, the SCAN is associated with the entire cluster, rather than an individual node, and associated with multiple IP addresses, not just one address.
SCAN works as an independent handler for the entire cluster — it acts on client’s behalf during connection request since it knows all cluster services and it’s available, least loaded nodes:
The SCAN works by being able to resolve to multiple IP addresses reflecting multiple listeners in the cluster handling public client connections. When a client submits a request, the SCAN listener listening on a SCAN IP address and the SCAN port is contracted on a client’s behalf. Because all services on the cluster are registered with the SCAN listener, the SCAN listener replies with the address of the local listener on the least-loaded node where the service is currently being offered. Finally, the client establishes connection to the service through the listener on the node where service is offered. All of these actions take place transparently to the client without any explicit configuration required in the client.
Bottom line – use SCAN – it simplifies cluster management:
Because the SCAN addresses resolve to the cluster, rather than to a node address in the cluster, nodes can be added to or removed from the cluster without affecting the SCAN address configuration.
Reference: D.1.3.5 About the SCAN
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Vitaliy Mogilevskiy September 10, 2009
Posted In: RAC
Tags: 11gR2, SCAN, single client access name, vip
Hi,
Is it possible to implement SCAN functionality with using DNS or GNS, I mean over entries in /etc/hosts file ?
If yes, how can we do this ?
Regards
Shine
Sorry for the typo, I mean WITHOUT using DNS or GNS in my last response
For production you will have to use DNS/GNS. If you are just trying to setup a test install then you could simply put ONE scan address into /etc/hosts and make sure your /etc/nsswitch.conf reads “hosts: files dns”. Not sure if it will work but you could try …
If you do not specify the SCAN in DNS, the OUI for grid infrastructure will fail at the end of the installation with:
———————————————-
ERROR:
PRVF-4657 : Name resolution setup check for “vmlinux-cluster-scan” (IP address: 192.168.1.184) failed
ERROR:
PRVF-4664 : Found inconsistent name resolution entries for SCAN name “vmlinux-cluster-scan”
———————————————-
The OUI uses nslookup to validate the SCAN – remember that nslookup is a DNS utility and does not read /etc/hosts so making the change in /etc/nsswitch.conf will have no affect.
As per Metalink Doc ID: 887471.1, you can safely ignore this error and continue with the installation, however, Oracle strongly suggests you configure the SCAN in DNS.
If you want to make it through the grid infrastructure install without receiving the PRVF-4657 / PRVF-4664 failure, perform the following hack before running the OUI on all nodes in the cluster. Note that I am simply defining a single IP address (192.168.1.184) for a scan named vmlinux-cluster-scan and where my DNS server is 24.154.1.34:
———————————————————
mv /usr/bin/nslookup /usr/bin/nslookup.original
cat < /usr/bin/nslookup
#!/bin/bash
HOSTNAME=\${1}
if [[ \$HOSTNAME = “vmlinux-cluster-scan” ]]; then
echo “Server: 24.154.1.34”
echo “Address: 24.154.1.34#53”
echo “Non-authoritative answer:”
echo “Name: vmlinux-cluster-scan”
echo “Address: 192.168.1.184”
else
nslookup.original \$HOSTNAME
fi
EOF
chmod 755 /usr/bin/nslookup
———————————————————
+—————————————————————+
| RUN CLUSTER VERIFICATION UTILITY – PASSED |
+—————————————————————+
[grid@vmlinux1 ~]$ cluvfy comp scan -verbose
Verifying scan
Checking Single Client Access Name (SCAN)…
SCAN VIP name Node Running? ListenerName Port Running?
—————- ———— ———— ———— ———— ————
vmlinux-cluster-scan vmlinux1 true LISTENER 1521 true
Checking name resolution setup for “vmlinux-cluster-scan”…
SCAN Name IP Address Status Comment
———— ———————— ———————— ———-
vmlinux-cluster-scan 192.168.1.184 passed
Verification of SCAN VIP and Listener setup passed
Verification of scan was successful.
Hi,
Our product support 11gR2 DB or higher.in my installation of the product my product installer need DB configuration parameter. i have a 11gR2 RAC setup. when my prod ask for db, i choose the RAC config and next screen it ask “provide RAC db in host1:port1:sid1,host2:port2:sid2”.
Is it the right behavior of the installer or it should as the SCAN parameter ?
plz suggest
@Patra
My suggestion would be to design your installation to use TNS Alias and let the DBA define how your product connects to the database. It will simplify your and DBA’s life. I come across too many products that try to be too clever during installation which results in horrible experience. Let the person doing the installation make these decisions.
-HTH
Thanks MVE,
Our product is a brand new one and its not in Market.its on still development. And as in its document says that it support only 11gR2 or higher DB not less versions.
I need a recommendation , as the product doesn’t support even 11gR1 DB then why should we go the traditional type “host1:port1:sid1,host2:port2:sid2” for RAC input. Simple we can put in the screen the SCAN name and let the RAC DB handle all. i.e, a single connect string.
@Patra
There’s nothing traditional in what you are trying to do with “host1:port1:sid1,host2:port2:sid2”. It’s just too basic of an approach and will not fit a real production shop setup. I know it would not have a chance in my shop.
Again, let the guy managing the database make the decision of how your product connects to his database. The way you do that is by accepting a TNS alias from him during installation process instead of trying to be too clever and figuring it out on your own.
Not all 11gR2 databases will have SCAN addresses, not all 11gR2 databases will be RAC. The only thing you can pretty much count on 100% is that every production, serious database will have a TNS alias defined for it’s connection and even if it didn’t it’s not too difficult for a DBA to define one.
-HTH
Thanks MVE,
i was going “http://www.dbatoolz.com/page/2”. so thought that implementing SCAN will be a good. I will consult with the DBA that whats the production configuration they have ?
Just for my knowledge, i face anther prob that i cant connect the db using SID . but i can connect the db user through service name.
when i connect a user using SID getting an error ora-12514.
I have a 11gr2 grid infrastructure/ RAC db setup. I have done all the required as the installation procedure done. could you please reply where and which entries to be need to modify so that i can access through SID.
As it a basic configuration prob .
@Patra
Scan addresses are an optional configuration — you cannot rely on it being available in every shop/database.
The reason you cannot connect using SID but can using SERVICE NAME is because ORACLE will automatically register SERVICE NAME of the database with the LOCAL listener but it doesn’t do that with the SID.
To connect via SID it needs to be defined in the listener.ora file on the database server (look up SID_LIST_LISTENER in the documentation). Here’s an example:
SID_LIST_LISTENER = (SID_LIST = (SID_DESC = (GLOBAL_DBNAME = MYDB.MYDOMAIN.COM) (ORACLE_HOME = /path/to/oracle/home) (SID_NAME = MYSID) ) )-HTH
I want to configure only scan with dns. I do not want to use gns. How many files should i modify for DNS? How many Physical and Public IPs do i need for two nodes cluster? Please help me with the number of IPs to be used and what should I tell my unix administrator about scan setup? I am really confused in this and I wasted my two days in the setup with no success..Please help me..any help is greatly appreciated.
Hi
I am not clear about SCAN IP ADDRESS. I have two node RAC under 10g. I have
Node A: public IP address
Private IP address
vip IP address
Node B Public Ip address
Private ip address
vip ip address
For scan IP address: What three IP addresses I need, because I have to tell my network Admin to create three round robin ip address of what node.Please be specific for the answer.
Thanks
MMC
@Chaudhry M
SCAN name should be associated with at least three IP addresses using DNS round-robin resolution.
So to answer your question — even for a TWO node cluster you should have your NETWORK ADMIN create a round-robin DNS entry for a SCAN name such as “mycluster-scan.domain.com” pointing to 3 unassociated IP addresses. Once you complete 11gR2 CLUSTER install it will auto-magically bind on these IP’s similarly to the way it binds to VIP addresses.
NOTE the following:
-HTH
Hi
Thank You for your response.
Will it be three IP addresses on each node on the same subnet as public network, because I have one b public network on each node. So total 6 ip address for two nodes.
thanks
MMC
@Chaudhry
Think of SCAN addresses this way — they are per CLUSTER not per NODE, so it’s best to forget about the number of nodes you have and instead think of “I have a cluster and it needs 3 SCAN addresses and they should be on the same subnet as my public IPs”.
-HTH
– Vitaliy
Hi
Thank You so mush. Now, it is clear to me.
Thanks
MMC
Hi Vitaliy,
I read your suggestion in 10th reply regarding why need to use “SERVICE NAME” instead of “SID”. This is true for JDBC connection like SQL*Developer.
As you said that we need to add one more clause for SID_Name in listener.ora file.
Now, In my case I am using SCAN (not GNS) and I have installed 11gR2. I have two node cluster setup. I have two ora file one name is listener.ora and another is endpoint_listener.ora file. Now, which file I need to make change and do I need to make changes for both the nodes?
please help me out…
Thanks…
@Suchi
Non default SID definitions go into the listener.ora files. Note that SID based connections are not “RAC aware”, in other words they are specific to the node you configure them on and will never failover.
If you just want to connect to a specific RAC node’s ORACLE_SID you don’t even need to configure anything on the rac node itself — it should work out of the box with the default listener configuration. All you have to do is configure a TNS alias on the client side as follows:
SIDNAME = (DESCRIPTION= (ADDRESS=(PROTOCOL=tcp)(HOST=rachost-vip)(PORT=1521)) (CONNECT_DATA=(SID=SIDNAME)) )Make sure the SIDNAME is the actual ORACLE_SID that’s defined on the rac node.
Then use this alias when making connections:
HTH,
– Vitaliy
Chaudhry,
Thanks for SCAN info. Another question…if I have more than 1 database on this 2 node RAC cluster, do I need another SCAN name with 3 IP’s to have the load balance for this app?
@Sri
SCAN names are defined per cluster, you can have as many databases on a cluster, so no, you don’t need a separate SCAN name for a second database.
PS: My name is Vitaliy
not Chaudhry.
What is about GNS IP?
I installed database and GI with 1 SCAN IP address. After the successful installation, I added 2 more IPs to do the round robin on the DNS. My question is how can I get the IPs to bind or register so that it shows up when I do “srvctl config scan” and “srvctl config scan_listner”. Currently only my original scan listener is show up. Thanks.
Hello,
You were saying that you can connect via a SCAN, but using a SID if that SID is listed in the listener.ora on the database machine. Is there any way using a query to determine what values are currently listed in listener.ora?
@EB you can only “guess it” — there’s no guarantee it’s listed in listener.ora:
select instance_name from v$instance;
You explained well about SCAN concept. Good to read and understand…
Hi Vitaliy,
You said “the SCAN listener replies with the address of the local listener on the least-loaded node where the service is currently being offered”. How does Scan listener resolve to the local listener. Does Scan listener use “endpoints_listener.ora” to handout the local VIP to the client requesting connection?
I understood the concept of scan listener, but still not sure how connection is handed to local VIP (instance) after determining least-loaded node.
Thanks
Vikas
@Vikas
SCAN listener will actually be running on the clustered nodes (the clusterware will automatically bind SCAN IPs to the local interface on selected nodes); then a client will be connecting directly through the SCAN listener. For example:
Notice that in the HOST directive we no longer list the VIPs — just one SCAN name.
-HTH
Does it mean a client will need to connect to the scan lister first, then connect to a least loaded local listener via the scan listener? Will this cause delay for a client to connect to a 11gR2 RAC databases compared with a non-RAC database or prior 11gR2 RAC databases (by using VIP) since it seems a client needs make two connections in order to connect to a instance?
Thanks!
@Angela
The SCAN listener will connect a CLIENT directly to the RAC node (not another listener) and yes it will go through the same selection process of evaluating which INSTANCE/node the connection will be going to.
-HTH
I have SCAN name associated with three IP addresses using DNS round-robin resolution.
When execute root.sh in the first node I dont have problem,
but when execute root.sh in the second node fails because the Ip’s to SCAN there are asigned in the first node, for this reason this Ip’s can’t mount in the second node and display this message:
CRS-5005: IP Address: 172.16.10.196 is already in use in the network
CRS-2674: Start of ‘ora.scan1.vip’ on ‘node2’ failed
CRS-2632: There are no more servers to try to place resource ‘ora.scan1.vip’ on that would satisfy its placement policy
PRCR-1079 : Failed to start resource ora.scan2.vip
CRS-5005: IP Address: 172.16.10.197 is already in use in the network
CRS-2674: Start of ‘ora.scan2.vip’ on ‘node2’ failed
CRS-2632: There are no more servers to try to place resource ‘ora.scan2.vip’ on that would satisfy its placement policy
PRCR-1079 : Failed to start resource ora.scan3.vip
CRS-5005: IP Address: 172.16.10.198 is already in use in the network
CRS-2674: Start of ‘ora.scan3.vip’ on ‘node2’ failed
I want to discuss and setup multiple listeners, before we discuss why I need to setup. Here is my situation
Reason: 3 Node RAC, 10 databases running for 20 applications
My Thougts: In the past if we use more connections on single port, there is potential issue that port may get stale and application will not accept any more connections, which force the listener and apps layer reboot. To avoid we come up with multiple listeners with different port per listener.
I’m looking for: Why local_listener showing both default LISTENER and also MYDB listener. And how should tnsnames.ora entry must have a scan as HOST name or VIP?
Also when trace listener, that is showing different port and host name , please see details belowG
My Test Case: As per 11gR2 documentation and also following 2 metalink notes 1070607.1 and 557946.1
I create different listener called LISTENER_MYDB1522 under GRID HOME.
in the pfile/spfile have changed local_listener=’LISTENER_MYDB1522′ but when I start database that looks as below and remote_listener looks just fine
DON’T KNOW WHY I’M SEEING BOTH default LISTENER and MYDB LISTENER
################################################################################
NAME TYPE VALUE
——————————————————————————–
———–
——————————————————————————–
local_listener string (DESCRIPTION=(ADDRESS_LIST=(AD
DRESS=(PROTOCOL=TCP)(HOST=stra
c201a-vip)(PORT=1521))(ADDRESS
=(PROTOCOL=TCP)(HOST=strac201a
-vip)(PORT=1522))))
SQL> show parameter remote_listener
NAME TYPE VALUE
——————————————————————————–
———–
——————————————————————————–
remote_listener string strac201-scan.frxntnyc.frx2.co
m:1521
################################################################################
in GRID HOME
and my listener.ora looks like
################################################################################
LISTENER_MYDB1522=(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=IPC)(KEY=LISTENER_MYDB1522)))) # line added by Agent
LISTENER=(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=IPC)(KEY=LISTENER)))) # line added by Agent
LISTENER_SCAN3=(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=IPC)(KEY=LISTENER_SCAN3)))) # line added by Agent
LISTENER_SCAN2=(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=IPC)(KEY=LISTENER_SCAN2)))) # line added by Agent
LISTENER_SCAN1=(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=IPC)(KEY=LISTENER_SCAN1)))) # line added by Agent
ENABLE_GLOBAL_DYNAMIC_ENDPOINT_LISTENER_SCAN1=ON # line added by Agent
ENABLE_GLOBAL_DYNAMIC_ENDPOINT_LISTENER_SCAN2=ON # line added by Agent
ENABLE_GLOBAL_DYNAMIC_ENDPOINT_LISTENER_SCAN3=ON # line added by Agent
ENABLE_GLOBAL_DYNAMIC_ENDPOINT_LISTENER=ON # line added by Agent
ENABLE_GLOBAL_DYNAMIC_ENDPOINT_LISTENER_MYDB1522=ON # line added by Agent
################################################################################
endpoint_listener.ora is below
in GRID HOME
################################################################################
LISTENER_MYDB1522_STRAC201A=(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=strac201a-vip)(PORT=1522))(ADDRESS=(PROTOCOL=TCP)(HOST=172.24.21.89)(PO
RT=1522)(IP=FIRST)))) # line added by Agent
LISTENER_STRAC201A=(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=strac201a-vip)(PORT=1521))(ADDRESS=(PROTOCOL=TCP)(HOST=172.24.21.89)(PORT=1521)(
IP=FIRST)))) # line added by Agent
################################################################################
TNSNAMES.ORA
##############################################################################
MYDB1522 =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = strac201-scan.frxntnyc.frx2.com)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = MYDB1522)
)
)
##############################################################################
Listener.log
#################################################################################
28-JAN-2011 11:34:06 * trc_level * 0
28-JAN-2011 11:34:11 * (CONNECT_DATA=(SERVER=DEDICATED)(SERVICE_NAME=MYDB1522)(CID=(PROGRAM=c:\oracle\ora102\bin\sqlplus.exe)(HOST=ECVN-TPCONS4)(USER=kthoka))(INSTANCE_NAME=MYTSTDB1)) * (ADDRESS=(PROTOCOL=tcp)(HOST=172.27.31.234)(PORT=2238)) * establish * MYDB1522 * 0
#################################################################################
@Krishna
Your solution of having multiple listeners on the same host to alleviate issues with too many connections to a single listener is not a good idea. This type of problem should be solved using connection pooling at the application layer.
-HTH
@Carlos
Make sure the IPs used for SCAN are not the same used for your VIP.
-HTH
Hello MVE,
thank you for your response,
the three scan IP are differents to VIP Ip. what another thing could generate this problem?
can we use both scan and vip in the client side to connect. we don’t have the option for dns. we are doing with one scan ip in etc/hosts. due to bug with crsd got rebooted. in srvctl commands it shows every thing up nut application people were not able to connect. telnet was not working for that port. application sees no listner error. after bouncing scan listner every thing went to normal.
Carlos,
SCANs and VIP IPs are in-depended to each other…
SCAN
3 SCAN IPs for considering load balancing (round robin method) and HA requirement regardless of the number of servers in the Cluster
Using SCAN, you can add or delete node from Cluster without modifying the connection string
If you are using SCAN then u will notice HOST=myServer.scan.domain.com in TNS names file.. i.e not depended to any physical address of nodes in cluster
VIP
VIP IPs for IP failover and use 1:1 ratio in Cluster env.
I’m trying to set up a 2-node 11.2 RAC on my pc with two VMs (VMWare). I’m not using dns for SCAN. I’m getting:
INS-40724 No locally defined network matches the SCAN VIP subnet.
My subnets are:
VMnet1(Host-only) 172.16.100.0 – for interconnects
VMnet8(NAT) 192.168.78.0 – for host ip, vip, scan
SCAN VIP (in /etc/hosts): 192.168.78.71
ifconfig
eth0 Link encap:Ethernet HWaddr 00:0C:29:D7:3F:06
inet addr:192.168.78.51 Bcast:192.168.78.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:634 errors:0 dropped:0 overruns:0 frame:0
TX packets:276 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:174995 (170.8 KiB) TX bytes:30562 (29.8 KiB)
eth1 Link encap:Ethernet HWaddr 00:0C:29:D7:3F:10
inet addr:172.16.100.51 Bcast:172.16.100.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:368 errors:0 dropped:0 overruns:0 frame:0
TX packets:89 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:37958 (37.0 KiB) TX bytes:13105 (12.7 KiB)
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:1906 errors:0 dropped:0 overruns:0 frame:0
TX packets:1906 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:2407347 (2.2 MiB) TX bytes:2407347 (2.2 MiB)
I even tried your hack of nslookup:
nslookup collab-scan
Server: 192.168.78.2
Address: 192.168.78.2#53
Non-authoritative answer:
Name: collab-scan
Address: 192.168.78.71
Still getting the same error. What am I missing?
Mark,
What do you get when running “./runcluvfy.sh stage -pre crsinst -n rac1,rac2” ?
– Vitaliy
Hi Vitaliy,
I was getting this error when using Typical Install option. I tried custom install and no errors. So it doesn’t seem to be related to my configuration, maybe the bug in the installer.
Vitaliy,
My installation is stuck on this message: “NS-40724 No locally defined network matches the SCAN VIP subnet.” and I can’t seem to get past it.
Three ip addresses for the SCAN are set up with our DNS. If I do a nslookup, all three of them are returned. No errors in my cluvfy output. I have tried with the SCAN entries in the /etc/hosts and not in the /etc/hosts file. Every thing “appears” to be set up as expected, but that stinking error keeps popping up.
Any other ideas before I pull the rest of my hair out?
Andrew
@Andrew
The SCAN IP addresses must be on the same subnet/network as your Public/VIP addresses. ClusterWare will actually bind your interfaces to the three SCAN IPs during installation and if your public NIC is not plugged in to the same subnet where your SCAN IPs are defined — it can’t be done.
HTH,
– Vitaliy
Vitaliy,
Thank you for getting back to me.
My sysadmin has verified that our network configuration is correct. This smells like a bug (as Mark stated above).
Andrew
@Andrew
Did you try what Mark did? (Switch install types). Are you installing 11gR2-base or 11gR2-P1? P1 has a known issue with enabling multicast but I haven’t seen the issue you are experiencing as of yet (I’ve done a number of installs on Oracle EL/RHEL).
Regards,
– Vitaliy
@Andrew
One more thing I forgot to mention — make sure to verify which Interface is being picked by the installer for Private and which for Public — because the installer can and does sometimes pick the wrong one. I think the button is called “Identify Network Interfaces”:
Regards,
– Vitaliy
Vitaliy,
I am not sure what “custom” installation Mark was referencing. It will allow me to install the software only, but I wanted to upgrade our existing environment. I don’t see the “Identify Network Interfaces”, so maybe that is an option for a fresh installation?
Regards,
Andrew
@Andrew
The Identify Network Interfaces is on the same page where you specify the name of the cluster/SCAN address and where you define the nodes.
Regards,
– Vitaliy
Vitaliy,
For me, it does not appear on that page. I am upgrading an existing environment – does that make a difference?
Andrew
@Andrew
What version are you upgrading from?
– Vitaliy
Vitaliy,
Upgrading from 11.1.0.7 to 11.2.0.2.
Andrew
@Andrew
I haven’t done this particular upgrade. However, I actually had to bail from 11.2.0.2 install recently and went with 11.2.0.1 due to Multicast issue (11.2.0.2 uses Multicast on the interconnect and if your switch doesn’t support it you are out of luck). I also clearly remember 11.2.0.2 getting our interfaces confused while 11.2.0.1 figured them out correctly. So it’s entirely possible that 11.2.0.2 has some issues and perhaps it makes sense to try 11.2.0.1 instead.
HTH,
– Vitaliy
Vitaliy,
I am going to log an SR with Oracle support and see what the story is. I downloaded the mcasttest code to test the multicast and it comes back as successful. However, I found out that our firewall does not support multicast – so maybe that is the problem.
Thanks again for your help!
Andrew
P.S. If I find out anything worthwhile, I will post back here.
Sounds good Andrew — let us know what happens.
Regards,
– Vitaliy
I have installed 11gR2 RAC with 3 nodes
I have configured TNS like below on client machine
RACT =
(DESCRIPTION =
(ENABLE=BROKEN)
(ADDRESS = (PROTOCOL = TCP)(HOST = camvlract-scan.emea.ind.com)(PORT = 1521))
(LOAD_BALANCE = yes)
(failover = yes)
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = RACT)
(failover_mode =
(type = session)
(method = basic)
(retries = 180)
(delay = 5)
)
)
)
RACT1 =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = camvlract1v.emea.ind.com)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = RACT)
(INSTANCE_NAME = RACT1)
)
)
same to connect to other individual nodes
when i give sqlplus sys/sys@RACT1 as sysdba from App server it is working fine
when give execute- sqlplus SYS/sys@//camvlract1.emea.ind.com:1521/RACT1 as sysdba
it is failing
$ sqlplus SYS/sys@//camvlract1.emea.ind.com:1521/RACT1 as sysdba
SQL*Plus: Release 11.2.0.1.0 Production on Wed Jun 8 19:51:20 2011
Copyright (c) 1982, 2009, Oracle. All rights reserved.
ERROR:
ORA-12541: TNS:no listener
Enter user-name:
what can be the problem?
Please can you kindly help with my 11gR2 RAC installation. I have successfully installed the Grid Infrastructure and ran cluvfy comp clumgr -n nodelist to verify cluster manager integrity. My nslookup resolves to 3 scan entries. However, when I am installing the RAC Software ( or any other options) the OUI does not list any of my 2 nodes and I donot have any errors showing. Any help will be appreciated as I have done all the network checks with metalink docs and nothing seems wrong.
Ireti.
Hi I am trying to install grid on sles machine , almost everything went through fine but it fails @ scan name resolution.
/u01/app/crs/product/11.2.0/crs/bin/cluvfy comp scan -verbose
Verifying scan
Checking Single Client Access Name (SCAN)…
SCAN VIP name Node Running? ListenerName Port Running?
—————- ———— ———— ———— ———— ————
sles11-scan.bgl.avamar.emc sles11rac1 true LISTENER 1521 true
Checking name resolution setup for “sles11-scan.bgl.avamar.emc”…
SCAN Name IP Address Status Comment
———— ———————— ———————— ———-
sles11-scan.bgl.avamar.emc 10.31.140.116 failed DNS Entry
sles11-scan.bgl.avamar.emc 10.31.140.31 passed
sles11-scan.bgl.avamar.emc 10.31.140.114 failed DNS Entry
ERROR:
PRVF-4664 : Found inconsistent name resolution entries for SCAN name “sles11-scan.bgl.avamar.emc”
Verification of SCAN VIP and Listener setup failed
Verification of scan was unsuccessful on all the specified nodes.
===============================
but strange thing is nslookup returns all the 3 scan ips
oracle@sles11rac1:/u01/app/crs/product/11.2.0/crs/bin> /opt/oracle/grid/stage/cvu/cv/remenv/exectask.sh -runexe /usr/bin/nslookup sles11-scan
/usr/bin/nslookup sles11-scan Server: 10.31.142.21
Address: 10.31.142.21#53
Name: sles11-scan.bgl.avamar.emc
Address: 10.31.140.31
Name: sles11-scan.bgl.avamar.emc
Address: 10.31.140.114
Name: sles11-scan.bgl.avamar.emc
Address: 10.31.140.116
some help on this would be very helpful.
Thanks.
hi,
i have a working 3-node 11g R2 with the GNS enabled to managed my SCAN.
the cluster is connected to a network with clients that could not reach the SCAN.
is it possible to bring up a new SCAN using different domain to serve the other network?
of course the IPs would be entirely different from the IPs on the existing SCAN.
thank you very much for any information you would share.
@Niko Koki
That’s not supported. SCAN and VIP must be on the same network.
@iresh
Not sure what the problem is. Please review ML Note: 887471.1 — it might help.
hi mve,
thank you very much for the quick reply.
i really appreciate it.
have a great weekend.
I have successfully installed 2 Node RAC with Database and its connecting now.(without GNS)
But now i see SCAN IP is defined only on one Node
+ASM1 /oravl01/oracle > srvctl config scan
SCAN name: indlinrac1, Network: 1/10.19.52.0/255.255.255.192/eth0
SCAN VIP name: scan1, IP: /indlinrac1.corp.amdocs.com/10.19.52.49
it will give output from node 1 only with ip 10.19.52.49
+ASM1 /oravl01/oracle > nslookup indlinrac1
Server: 10.19.164.84
Address: 10.19.164.84#53
Name: indlinrac1.corp.amdocs.com
Address: 10.19.52.49
missing SCAN IP in /sbin/ifconfig for second node
In my tnsnames.ora LOAD_BALANCE = OFF
So is it ok to add SCAN IP on second node now in /sbin/ifconfig
Or i should leave it like this and deliver to customer
Hi MVE,
I think we’re having a problem similar to Carlos’ above. I installed our first 11gR2 Windows Server 2008 R2 two-node cluster using 3 SCAN addresses. The 3 addresses have bound to one of the nodes and (Microsoft default!) registered them to resolve to that node name in DNS. Aargh! What should I have done during installation to prevent this happening?
Thanks in advance.
i have a 2 node RAC (11.2.0.2) with 2 databases on it. SCAN is installed and functioning. I want to have a listener for each database i.e. 2 different listeners. Is it possible?
Dear!
I have two nodes cluster 11GR2 configured on windows.
On the second node sometimes the scan listner stops.
Hi,
We had Oracle 11gR2 RAC in a SAN environment on Windows 2008 R2 platform. It is now a production server. Presently, we are using Crossover cables for the Private IP’s on the two node. My question is will my server will work if I use switch instead of crossover cable? My plan is to take a downtime and then change the cable. IS IT OK TO DO SO? or shall i continue as it is with crossover cable?
Can I implement SCAN on the standalone 11gR2 server, in the case we convert to full rac later on so nothing will change on client connection.
On one client PC, a suffix added to DNS that allowed them to resolve the scan name and the three ips returned, but did not have a different suffix required to resolve the corresponding three -vip names. We kept getting a generic connection error until we added that.
My question is, is there a way to find out these -vip servers that were also required to be in DNS for the connection to work? Or, optionally, is there a way to force the Oracle client to use numbers, -n?, instead of names for the -vips?
Thx.