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Posted to user@cassandra.apache.org by Renato Perini <re...@gmail.com> on 2015/10/04 23:59:17 UTC
Cassandra Configuration VS Static IPs.
Is cassandra really supposed to have a static public IP for each and
single node in the cluster?
This seems to be expensive (static IPs are nor free neither cheap),
still the broadcast_rpc_address expects a static IP for client
communications (load balancing, contact points, etc.)
Is there some mechanism to determine a public IP at runtime?
Basically, I have nodes (machines) with dynamic public IPs and I cannot
embed them in the cassandra.yaml file because of their dynamic nature
(they change at each reboot).
Any solution to this?
Thanks.
Re: Cassandra Configuration VS Static IPs.
Posted by Jonathan Haddad <jo...@jonhaddad.com>.
Personally I wouldn't bother with a VPN. You can limit access to a group
of servers easily via security groups and not have a single point of
failure. I wrote a utility to manage this. If you're bringing up a new
VPC + Cassandra servers every day, you can trivially apply a set of rules
to your VPC:
http://rustyrazorblade.com/2014/06/an-introduction-to-roadhouse/
On Tue, Oct 6, 2015 at 10:30 AM Gene <gh...@gmail.com> wrote:
> Rather than using public IPs on the Cassandra nodes at all I would set up
> a VPN.
>
> 1. Make sure all Cassandra nodes are on the same private network with
> static IPs
> 2. Set up a new micro instance with a static public IP, make sure it has a
> static IP on the private network as well
> 3. Install OpenVPN on the new micro instance, configure it to tunnel
> traffic to that private network
> 4. Configure your cassandra nodes to permit access from this instance
> 5. Configure your workstation to make a VPN connection and use the static,
> private IPs of the cassandra nodes for your client connectivity
>
> -Gene
>
>
> On Sun, Oct 4, 2015 at 5:31 PM, Renato Perini <re...@gmail.com>
> wrote:
>
>> Jonathan, I have some difficulties in understanding what you're talking
>> about. A client is a program connecting to a cassandra instance. All it
>> needs to know is an IP, a keyspace and a table to operate. My client is
>> nothing more than a simple textual version of a program like datastax
>> devcenter. No "same dc" concepts are involved for using it.
>> As for AWS, I'm not changing anything. The instances, as I said multiple
>> times, don't have an elastic ip, so the public IP is dynamic. This means it
>> changes automatically at every reboot.
>>
>>
>> Il 05/10/2015 02:22, Jonathan Haddad ha scritto:
>>
>> If your client is in the same DC, then you shouldn't use *public* ip
>> addresses. If you're using a recent version of Cassandra you can just set
>> the listen_interface and rpc_interface to whatever network interface you've
>> got.
>>
>> If you're really changing IPs when you reboot machines (I have no idea
>> why you'd do this, AWS definitely doesn't work this way) then I think
>> you're going to hit a whole set of other issues.
>>
>>
>> On Sun, Oct 4, 2015 at 7:10 PM Renato Perini < <re...@gmail.com>
>> renato.perini@gmail.com> wrote:
>>
>>> Yes, the client uses the same datacenter (us-west-2).
>>> Maybe I haven't explained well the situation. I'm not asking to connect
>>> to nodes *without* using a static IP address, but allowing Cassandra to
>>> determine the current public address at the time of connection.
>>> Spark, for example, uses shell scripts for configuration, so the public
>>> IP (in AWS) can be assigned using the command `curl
>>> http://169.254.169.254/latest/meta-data/public-ipv4`, whatever it is at
>>> the time of boot.
>>> Cassandra uses a yaml file for the main configuration, so this is
>>> impossibile to achieve. Basically I would like to make the client connect
>>> correctly on all nodes using their public IPs without being required to
>>> know them (the client would discover them dynamically while connecting).
>>>
>>>
>>>
>>> Il 05/10/2015 00:55, Jonathan Haddad ha scritto:
>>>
>>> So you're not running the client in the same DC as your Cassandra
>>> cluster. In that case you'll need to be able to connect to the public
>>> address of all the nodes. Technically you could have a whitelist and only
>>> connect to 1, I wouldn't recommend it.
>>>
>>> This is no different than any other database in that you would need a
>>> public address to be able to connect to the servers from a machine not in
>>> your datacenter. How else would you connect to them if you don't provide
>>> access?
>>>
>>> On Sun, Oct 4, 2015 at 6:35 PM Renato Perini <re...@gmail.com>
>>> wrote:
>>>
>>>> Seems to be not the case when connecting to my (single) data center
>>>> using the java connector with a small client I have developed for testing.
>>>> For the broadcast_rpc_address I have configured the local IP of the
>>>> nodes. The cluster works fine and nodes communicates fairly well using
>>>> their local IPs. When I connect to a node (let's say node 1) from the
>>>> outside using the java driver and the node's public IP, the cluster
>>>> discovery uses internal IPs for contacting other nodes, leading to
>>>> (obviously) errors.
>>>>
>>>> As for AWS, Elastic IPs are free as long as they're associated to an
>>>> instance and the machines are up 24h/7. I have to shut down the machines
>>>> during the night for various reasons, so unfortunately they're not totally
>>>> free for my use case.
>>>>
>>>>
>>>>
>>>> Il 05/10/2015 00:04, Jonathan Haddad ha scritto:
>>>>
>>>> Public IP? No, not required unless you're running multiple DCs.
>>>>
>>>> Where are you running a DC that IPs aren't cheap? If you're in AWS
>>>> they're basically free (or at least the cheapest section of your bill by
>>>> far)
>>>>
>>>>
>>>>
>>>> On Sun, Oct 4, 2015 at 5:59 PM Renato Perini <re...@gmail.com>
>>>> wrote:
>>>>
>>>>> Is cassandra really supposed to have a static public IP for each and
>>>>> single node in the cluster?
>>>>> This seems to be expensive (static IPs are nor free neither cheap),
>>>>> still the broadcast_rpc_address expects a static IP for client
>>>>> communications (load balancing, contact points, etc.)
>>>>> Is there some mechanism to determine a public IP at runtime?
>>>>>
>>>>> Basically, I have nodes (machines) with dynamic public IPs and I cannot
>>>>> embed them in the cassandra.yaml file because of their dynamic nature
>>>>> (they change at each reboot).
>>>>> Any solution to this?
>>>>>
>>>>> Thanks.
>>>>>
>>>>
>>>>
>>>
>>
>
Re: Cassandra Configuration VS Static IPs.
Posted by Gene <gh...@gmail.com>.
Rather than using public IPs on the Cassandra nodes at all I would set up a
VPN.
1. Make sure all Cassandra nodes are on the same private network with
static IPs
2. Set up a new micro instance with a static public IP, make sure it has a
static IP on the private network as well
3. Install OpenVPN on the new micro instance, configure it to tunnel
traffic to that private network
4. Configure your cassandra nodes to permit access from this instance
5. Configure your workstation to make a VPN connection and use the static,
private IPs of the cassandra nodes for your client connectivity
-Gene
On Sun, Oct 4, 2015 at 5:31 PM, Renato Perini <re...@gmail.com>
wrote:
> Jonathan, I have some difficulties in understanding what you're talking
> about. A client is a program connecting to a cassandra instance. All it
> needs to know is an IP, a keyspace and a table to operate. My client is
> nothing more than a simple textual version of a program like datastax
> devcenter. No "same dc" concepts are involved for using it.
> As for AWS, I'm not changing anything. The instances, as I said multiple
> times, don't have an elastic ip, so the public IP is dynamic. This means it
> changes automatically at every reboot.
>
>
> Il 05/10/2015 02:22, Jonathan Haddad ha scritto:
>
> If your client is in the same DC, then you shouldn't use *public* ip
> addresses. If you're using a recent version of Cassandra you can just set
> the listen_interface and rpc_interface to whatever network interface you've
> got.
>
> If you're really changing IPs when you reboot machines (I have no idea why
> you'd do this, AWS definitely doesn't work this way) then I think you're
> going to hit a whole set of other issues.
>
>
> On Sun, Oct 4, 2015 at 7:10 PM Renato Perini < <re...@gmail.com>
> renato.perini@gmail.com> wrote:
>
>> Yes, the client uses the same datacenter (us-west-2).
>> Maybe I haven't explained well the situation. I'm not asking to connect
>> to nodes *without* using a static IP address, but allowing Cassandra to
>> determine the current public address at the time of connection.
>> Spark, for example, uses shell scripts for configuration, so the public
>> IP (in AWS) can be assigned using the command `curl
>> http://169.254.169.254/latest/meta-data/public-ipv4`, whatever it is at
>> the time of boot.
>> Cassandra uses a yaml file for the main configuration, so this is
>> impossibile to achieve. Basically I would like to make the client connect
>> correctly on all nodes using their public IPs without being required to
>> know them (the client would discover them dynamically while connecting).
>>
>>
>>
>> Il 05/10/2015 00:55, Jonathan Haddad ha scritto:
>>
>> So you're not running the client in the same DC as your Cassandra
>> cluster. In that case you'll need to be able to connect to the public
>> address of all the nodes. Technically you could have a whitelist and only
>> connect to 1, I wouldn't recommend it.
>>
>> This is no different than any other database in that you would need a
>> public address to be able to connect to the servers from a machine not in
>> your datacenter. How else would you connect to them if you don't provide
>> access?
>>
>> On Sun, Oct 4, 2015 at 6:35 PM Renato Perini <re...@gmail.com>
>> wrote:
>>
>>> Seems to be not the case when connecting to my (single) data center
>>> using the java connector with a small client I have developed for testing.
>>> For the broadcast_rpc_address I have configured the local IP of the
>>> nodes. The cluster works fine and nodes communicates fairly well using
>>> their local IPs. When I connect to a node (let's say node 1) from the
>>> outside using the java driver and the node's public IP, the cluster
>>> discovery uses internal IPs for contacting other nodes, leading to
>>> (obviously) errors.
>>>
>>> As for AWS, Elastic IPs are free as long as they're associated to an
>>> instance and the machines are up 24h/7. I have to shut down the machines
>>> during the night for various reasons, so unfortunately they're not totally
>>> free for my use case.
>>>
>>>
>>>
>>> Il 05/10/2015 00:04, Jonathan Haddad ha scritto:
>>>
>>> Public IP? No, not required unless you're running multiple DCs.
>>>
>>> Where are you running a DC that IPs aren't cheap? If you're in AWS
>>> they're basically free (or at least the cheapest section of your bill by
>>> far)
>>>
>>>
>>>
>>> On Sun, Oct 4, 2015 at 5:59 PM Renato Perini <re...@gmail.com>
>>> wrote:
>>>
>>>> Is cassandra really supposed to have a static public IP for each and
>>>> single node in the cluster?
>>>> This seems to be expensive (static IPs are nor free neither cheap),
>>>> still the broadcast_rpc_address expects a static IP for client
>>>> communications (load balancing, contact points, etc.)
>>>> Is there some mechanism to determine a public IP at runtime?
>>>>
>>>> Basically, I have nodes (machines) with dynamic public IPs and I cannot
>>>> embed them in the cassandra.yaml file because of their dynamic nature
>>>> (they change at each reboot).
>>>> Any solution to this?
>>>>
>>>> Thanks.
>>>>
>>>
>>>
>>
>
Re: Cassandra Configuration VS Static IPs.
Posted by Eric Stevens <mi...@gmail.com>.
Basically your client just needs a route to talk to the IP being broadcast
by each node. We do plenty in EC2 and we use the instance private IP in
the broadcast address. If you are doing multi-datacenter in EC2 it gets a
little harrier, where you need to use the public IP (but not necessarily
elastic IPs).
> A client is a program connecting to a cassandra instance. All it needs to
know is an IP, a keyspace and a table to operate.
More correctly it's talking to a Cassandra cluster; typically you'll
configure your client with several seed nodes, and the client will use
those to discover the topology of the rest of the cluster. Your client
should be able to talk to all the nodes in at least one DC (usually the
same physical as well as logical DC as the client). This helps any good
client which will attempt to route queries directly to the replicas for
each piece of data to save the cluster the overhead and increased latency
of coordinating reads and writes.
On Sun, Oct 4, 2015 at 6:41 PM Jonathan Haddad <jo...@jonhaddad.com> wrote:
> You've been talking about configuring static, public IPs. Public IPs are
> only needed if you want to connect to your Cassandra servers from a public
> network aka not from the same datacenter.
>
> AWS instances don't get a new IP on rebooting. The instance doesn't
> shutdown when you tell a server to reboot, it just keeps running & keeps
> the same IP.
>
> You can connect to the internal address (192.168.x.x) or (10.x.x.x.) if
> you're on the same network. That's not a public IP. You don't have to
> hard code an address in your yaml, you can just the rpc_interface and set
> it to eth0 (or whatever AWS uses by default for server's NIC).
>
> Also, you know you can control IP addresses in a VPC, right?
>
> On Sun, Oct 4, 2015 at 8:31 PM Renato Perini <re...@gmail.com>
> wrote:
>
>> Jonathan, I have some difficulties in understanding what you're talking
>> about. A client is a program connecting to a cassandra instance. All it
>> needs to know is an IP, a keyspace and a table to operate. My client is
>> nothing more than a simple textual version of a program like datastax
>> devcenter. No "same dc" concepts are involved for using it.
>> As for AWS, I'm not changing anything. The instances, as I said multiple
>> times, don't have an elastic ip, so the public IP is dynamic. This means it
>> changes automatically at every reboot.
>>
>>
>> Il 05/10/2015 02:22, Jonathan Haddad ha scritto:
>>
>> If your client is in the same DC, then you shouldn't use *public* ip
>> addresses. If you're using a recent version of Cassandra you can just set
>> the listen_interface and rpc_interface to whatever network interface you've
>> got.
>>
>> If you're really changing IPs when you reboot machines (I have no idea
>> why you'd do this, AWS definitely doesn't work this way) then I think
>> you're going to hit a whole set of other issues.
>>
>>
>> On Sun, Oct 4, 2015 at 7:10 PM Renato Perini <re...@gmail.com>
>> wrote:
>>
>>> Yes, the client uses the same datacenter (us-west-2).
>>> Maybe I haven't explained well the situation. I'm not asking to connect
>>> to nodes *without* using a static IP address, but allowing Cassandra to
>>> determine the current public address at the time of connection.
>>> Spark, for example, uses shell scripts for configuration, so the public
>>> IP (in AWS) can be assigned using the command `curl
>>> http://169.254.169.254/latest/meta-data/public-ipv4`, whatever it is at
>>> the time of boot.
>>> Cassandra uses a yaml file for the main configuration, so this is
>>> impossibile to achieve. Basically I would like to make the client connect
>>> correctly on all nodes using their public IPs without being required to
>>> know them (the client would discover them dynamically while connecting).
>>>
>>>
>>>
>>> Il 05/10/2015 00:55, Jonathan Haddad ha scritto:
>>>
>>> So you're not running the client in the same DC as your Cassandra
>>> cluster. In that case you'll need to be able to connect to the public
>>> address of all the nodes. Technically you could have a whitelist and only
>>> connect to 1, I wouldn't recommend it.
>>>
>>> This is no different than any other database in that you would need a
>>> public address to be able to connect to the servers from a machine not in
>>> your datacenter. How else would you connect to them if you don't provide
>>> access?
>>>
>>> On Sun, Oct 4, 2015 at 6:35 PM Renato Perini <re...@gmail.com>
>>> wrote:
>>>
>>>> Seems to be not the case when connecting to my (single) data center
>>>> using the java connector with a small client I have developed for testing.
>>>> For the broadcast_rpc_address I have configured the local IP of the
>>>> nodes. The cluster works fine and nodes communicates fairly well using
>>>> their local IPs. When I connect to a node (let's say node 1) from the
>>>> outside using the java driver and the node's public IP, the cluster
>>>> discovery uses internal IPs for contacting other nodes, leading to
>>>> (obviously) errors.
>>>>
>>>> As for AWS, Elastic IPs are free as long as they're associated to an
>>>> instance and the machines are up 24h/7. I have to shut down the machines
>>>> during the night for various reasons, so unfortunately they're not totally
>>>> free for my use case.
>>>>
>>>>
>>>>
>>>> Il 05/10/2015 00:04, Jonathan Haddad ha scritto:
>>>>
>>>> Public IP? No, not required unless you're running multiple DCs.
>>>>
>>>> Where are you running a DC that IPs aren't cheap? If you're in AWS
>>>> they're basically free (or at least the cheapest section of your bill by
>>>> far)
>>>>
>>>>
>>>>
>>>> On Sun, Oct 4, 2015 at 5:59 PM Renato Perini <re...@gmail.com>
>>>> wrote:
>>>>
>>>>> Is cassandra really supposed to have a static public IP for each and
>>>>> single node in the cluster?
>>>>> This seems to be expensive (static IPs are nor free neither cheap),
>>>>> still the broadcast_rpc_address expects a static IP for client
>>>>> communications (load balancing, contact points, etc.)
>>>>> Is there some mechanism to determine a public IP at runtime?
>>>>>
>>>>> Basically, I have nodes (machines) with dynamic public IPs and I cannot
>>>>> embed them in the cassandra.yaml file because of their dynamic nature
>>>>> (they change at each reboot).
>>>>> Any solution to this?
>>>>>
>>>>> Thanks.
>>>>>
>>>>
>>>>
>>>
>>
Re: Cassandra Configuration VS Static IPs.
Posted by Jonathan Haddad <jo...@jonhaddad.com>.
You've been talking about configuring static, public IPs. Public IPs are
only needed if you want to connect to your Cassandra servers from a public
network aka not from the same datacenter.
AWS instances don't get a new IP on rebooting. The instance doesn't
shutdown when you tell a server to reboot, it just keeps running & keeps
the same IP.
You can connect to the internal address (192.168.x.x) or (10.x.x.x.) if
you're on the same network. That's not a public IP. You don't have to
hard code an address in your yaml, you can just the rpc_interface and set
it to eth0 (or whatever AWS uses by default for server's NIC).
Also, you know you can control IP addresses in a VPC, right?
On Sun, Oct 4, 2015 at 8:31 PM Renato Perini <re...@gmail.com>
wrote:
> Jonathan, I have some difficulties in understanding what you're talking
> about. A client is a program connecting to a cassandra instance. All it
> needs to know is an IP, a keyspace and a table to operate. My client is
> nothing more than a simple textual version of a program like datastax
> devcenter. No "same dc" concepts are involved for using it.
> As for AWS, I'm not changing anything. The instances, as I said multiple
> times, don't have an elastic ip, so the public IP is dynamic. This means it
> changes automatically at every reboot.
>
>
> Il 05/10/2015 02:22, Jonathan Haddad ha scritto:
>
> If your client is in the same DC, then you shouldn't use *public* ip
> addresses. If you're using a recent version of Cassandra you can just set
> the listen_interface and rpc_interface to whatever network interface you've
> got.
>
> If you're really changing IPs when you reboot machines (I have no idea why
> you'd do this, AWS definitely doesn't work this way) then I think you're
> going to hit a whole set of other issues.
>
>
> On Sun, Oct 4, 2015 at 7:10 PM Renato Perini <re...@gmail.com>
> wrote:
>
>> Yes, the client uses the same datacenter (us-west-2).
>> Maybe I haven't explained well the situation. I'm not asking to connect
>> to nodes *without* using a static IP address, but allowing Cassandra to
>> determine the current public address at the time of connection.
>> Spark, for example, uses shell scripts for configuration, so the public
>> IP (in AWS) can be assigned using the command `curl
>> http://169.254.169.254/latest/meta-data/public-ipv4`, whatever it is at
>> the time of boot.
>> Cassandra uses a yaml file for the main configuration, so this is
>> impossibile to achieve. Basically I would like to make the client connect
>> correctly on all nodes using their public IPs without being required to
>> know them (the client would discover them dynamically while connecting).
>>
>>
>>
>> Il 05/10/2015 00:55, Jonathan Haddad ha scritto:
>>
>> So you're not running the client in the same DC as your Cassandra
>> cluster. In that case you'll need to be able to connect to the public
>> address of all the nodes. Technically you could have a whitelist and only
>> connect to 1, I wouldn't recommend it.
>>
>> This is no different than any other database in that you would need a
>> public address to be able to connect to the servers from a machine not in
>> your datacenter. How else would you connect to them if you don't provide
>> access?
>>
>> On Sun, Oct 4, 2015 at 6:35 PM Renato Perini <re...@gmail.com>
>> wrote:
>>
>>> Seems to be not the case when connecting to my (single) data center
>>> using the java connector with a small client I have developed for testing.
>>> For the broadcast_rpc_address I have configured the local IP of the
>>> nodes. The cluster works fine and nodes communicates fairly well using
>>> their local IPs. When I connect to a node (let's say node 1) from the
>>> outside using the java driver and the node's public IP, the cluster
>>> discovery uses internal IPs for contacting other nodes, leading to
>>> (obviously) errors.
>>>
>>> As for AWS, Elastic IPs are free as long as they're associated to an
>>> instance and the machines are up 24h/7. I have to shut down the machines
>>> during the night for various reasons, so unfortunately they're not totally
>>> free for my use case.
>>>
>>>
>>>
>>> Il 05/10/2015 00:04, Jonathan Haddad ha scritto:
>>>
>>> Public IP? No, not required unless you're running multiple DCs.
>>>
>>> Where are you running a DC that IPs aren't cheap? If you're in AWS
>>> they're basically free (or at least the cheapest section of your bill by
>>> far)
>>>
>>>
>>>
>>> On Sun, Oct 4, 2015 at 5:59 PM Renato Perini <re...@gmail.com>
>>> wrote:
>>>
>>>> Is cassandra really supposed to have a static public IP for each and
>>>> single node in the cluster?
>>>> This seems to be expensive (static IPs are nor free neither cheap),
>>>> still the broadcast_rpc_address expects a static IP for client
>>>> communications (load balancing, contact points, etc.)
>>>> Is there some mechanism to determine a public IP at runtime?
>>>>
>>>> Basically, I have nodes (machines) with dynamic public IPs and I cannot
>>>> embed them in the cassandra.yaml file because of their dynamic nature
>>>> (they change at each reboot).
>>>> Any solution to this?
>>>>
>>>> Thanks.
>>>>
>>>
>>>
>>
>
Re: Cassandra Configuration VS Static IPs.
Posted by Renato Perini <re...@gmail.com>.
Jonathan, I have some difficulties in understanding what you're talking
about. A client is a program connecting to a cassandra instance. All it
needs to know is an IP, a keyspace and a table to operate. My client is
nothing more than a simple textual version of a program like datastax
devcenter. No "same dc" concepts are involved for using it.
As for AWS, I'm not changing anything. The instances, as I said multiple
times, don't have an elastic ip, so the public IP is dynamic. This means
it changes automatically at every reboot.
Il 05/10/2015 02:22, Jonathan Haddad ha scritto:
> If your client is in the same DC, then you shouldn't use *public* ip
> addresses. If you're using a recent version of Cassandra you can just
> set the listen_interface and rpc_interface to whatever network
> interface you've got.
>
> If you're really changing IPs when you reboot machines (I have no idea
> why you'd do this, AWS definitely doesn't work this way) then I think
> you're going to hit a whole set of other issues.
>
>
> On Sun, Oct 4, 2015 at 7:10 PM Renato Perini <renato.perini@gmail.com
> <ma...@gmail.com>> wrote:
>
> Yes, the client uses the same datacenter (us-west-2).
> Maybe I haven't explained well the situation. I'm not asking to
> connect to nodes *without* using a static IP address, but allowing
> Cassandra to determine the current public address at the time of
> connection.
> Spark, for example, uses shell scripts for configuration, so the
> public IP (in AWS) can be assigned using the command `|curl
> http://169.254.169.254/latest/meta-data/public-ipv4|`, whatever it
> is at the time of boot.
> Cassandra uses a yaml file for the main configuration, so this is
> impossibile to achieve. Basically I would like to make the client
> connect correctly on all nodes using their public IPs without
> being required to know them (the client would discover them
> dynamically while connecting).
>
>
>
> Il 05/10/2015 00:55, Jonathan Haddad ha scritto:
>> So you're not running the client in the same DC as your Cassandra
>> cluster. In that case you'll need to be able to connect to the
>> public address of all the nodes. Technically you could have a
>> whitelist and only connect to 1, I wouldn't recommend it.
>>
>> This is no different than any other database in that you would
>> need a public address to be able to connect to the servers from a
>> machine not in your datacenter. How else would you connect to
>> them if you don't provide access?
>>
>> On Sun, Oct 4, 2015 at 6:35 PM Renato Perini
>> <renato.perini@gmail.com <ma...@gmail.com>> wrote:
>>
>> Seems to be not the case when connecting to my (single) data
>> center using the java connector with a small client I have
>> developed for testing.
>> For the broadcast_rpc_address I have configured the local IP
>> of the nodes. The cluster works fine and nodes communicates
>> fairly well using their local IPs. When I connect to a node
>> (let's say node 1) from the outside using the java driver and
>> the node's public IP, the cluster discovery uses internal IPs
>> for contacting other nodes, leading to (obviously) errors.
>>
>> As for AWS, Elastic IPs are free as long as they're
>> associated to an instance and the machines are up 24h/7. I
>> have to shut down the machines during the night for various
>> reasons, so unfortunately they're not totally free for my use
>> case.
>>
>>
>>
>> Il 05/10/2015 00:04, Jonathan Haddad ha scritto:
>>> Public IP? No, not required unless you're running multiple
>>> DCs.
>>>
>>> Where are you running a DC that IPs aren't cheap? If you're
>>> in AWS they're basically free (or at least the cheapest
>>> section of your bill by far)
>>>
>>>
>>>
>>> On Sun, Oct 4, 2015 at 5:59 PM Renato Perini
>>> <renato.perini@gmail.com <ma...@gmail.com>>
>>> wrote:
>>>
>>> Is cassandra really supposed to have a static public IP
>>> for each and
>>> single node in the cluster?
>>> This seems to be expensive (static IPs are nor free
>>> neither cheap),
>>> still the broadcast_rpc_address expects a static IP for
>>> client
>>> communications (load balancing, contact points, etc.)
>>> Is there some mechanism to determine a public IP at runtime?
>>>
>>> Basically, I have nodes (machines) with dynamic public
>>> IPs and I cannot
>>> embed them in the cassandra.yaml file because of their
>>> dynamic nature
>>> (they change at each reboot).
>>> Any solution to this?
>>>
>>> Thanks.
>>>
>>
>
Re: Cassandra Configuration VS Static IPs.
Posted by Jonathan Haddad <jo...@jonhaddad.com>.
If your client is in the same DC, then you shouldn't use *public* ip
addresses. If you're using a recent version of Cassandra you can just set
the listen_interface and rpc_interface to whatever network interface you've
got.
If you're really changing IPs when you reboot machines (I have no idea why
you'd do this, AWS definitely doesn't work this way) then I think you're
going to hit a whole set of other issues.
On Sun, Oct 4, 2015 at 7:10 PM Renato Perini <re...@gmail.com>
wrote:
> Yes, the client uses the same datacenter (us-west-2).
> Maybe I haven't explained well the situation. I'm not asking to connect to
> nodes *without* using a static IP address, but allowing Cassandra to
> determine the current public address at the time of connection.
> Spark, for example, uses shell scripts for configuration, so the public IP
> (in AWS) can be assigned using the command `curl
> http://169.254.169.254/latest/meta-data/public-ipv4`, whatever it is at
> the time of boot.
> Cassandra uses a yaml file for the main configuration, so this is
> impossibile to achieve. Basically I would like to make the client connect
> correctly on all nodes using their public IPs without being required to
> know them (the client would discover them dynamically while connecting).
>
>
>
> Il 05/10/2015 00:55, Jonathan Haddad ha scritto:
>
> So you're not running the client in the same DC as your Cassandra
> cluster. In that case you'll need to be able to connect to the public
> address of all the nodes. Technically you could have a whitelist and only
> connect to 1, I wouldn't recommend it.
>
> This is no different than any other database in that you would need a
> public address to be able to connect to the servers from a machine not in
> your datacenter. How else would you connect to them if you don't provide
> access?
>
> On Sun, Oct 4, 2015 at 6:35 PM Renato Perini <re...@gmail.com>
> wrote:
>
>> Seems to be not the case when connecting to my (single) data center using
>> the java connector with a small client I have developed for testing.
>> For the broadcast_rpc_address I have configured the local IP of the
>> nodes. The cluster works fine and nodes communicates fairly well using
>> their local IPs. When I connect to a node (let's say node 1) from the
>> outside using the java driver and the node's public IP, the cluster
>> discovery uses internal IPs for contacting other nodes, leading to
>> (obviously) errors.
>>
>> As for AWS, Elastic IPs are free as long as they're associated to an
>> instance and the machines are up 24h/7. I have to shut down the machines
>> during the night for various reasons, so unfortunately they're not totally
>> free for my use case.
>>
>>
>>
>> Il 05/10/2015 00:04, Jonathan Haddad ha scritto:
>>
>> Public IP? No, not required unless you're running multiple DCs.
>>
>> Where are you running a DC that IPs aren't cheap? If you're in AWS
>> they're basically free (or at least the cheapest section of your bill by
>> far)
>>
>>
>>
>> On Sun, Oct 4, 2015 at 5:59 PM Renato Perini <re...@gmail.com>
>> wrote:
>>
>>> Is cassandra really supposed to have a static public IP for each and
>>> single node in the cluster?
>>> This seems to be expensive (static IPs are nor free neither cheap),
>>> still the broadcast_rpc_address expects a static IP for client
>>> communications (load balancing, contact points, etc.)
>>> Is there some mechanism to determine a public IP at runtime?
>>>
>>> Basically, I have nodes (machines) with dynamic public IPs and I cannot
>>> embed them in the cassandra.yaml file because of their dynamic nature
>>> (they change at each reboot).
>>> Any solution to this?
>>>
>>> Thanks.
>>>
>>
>>
>
Re: Cassandra Configuration VS Static IPs.
Posted by Renato Perini <re...@gmail.com>.
Yes, the client uses the same datacenter (us-west-2).
Maybe I haven't explained well the situation. I'm not asking to connect
to nodes *without* using a static IP address, but allowing Cassandra to
determine the current public address at the time of connection.
Spark, for example, uses shell scripts for configuration, so the public
IP (in AWS) can be assigned using the command `|curl
http://169.254.169.254/latest/meta-data/public-ipv4|`, whatever it is at
the time of boot.
Cassandra uses a yaml file for the main configuration, so this is
impossibile to achieve. Basically I would like to make the client
connect correctly on all nodes using their public IPs without being
required to know them (the client would discover them dynamically while
connecting).
Il 05/10/2015 00:55, Jonathan Haddad ha scritto:
> So you're not running the client in the same DC as your Cassandra
> cluster. In that case you'll need to be able to connect to the public
> address of all the nodes. Technically you could have a whitelist and
> only connect to 1, I wouldn't recommend it.
>
> This is no different than any other database in that you would need a
> public address to be able to connect to the servers from a machine not
> in your datacenter. How else would you connect to them if you don't
> provide access?
>
> On Sun, Oct 4, 2015 at 6:35 PM Renato Perini <renato.perini@gmail.com
> <ma...@gmail.com>> wrote:
>
> Seems to be not the case when connecting to my (single) data
> center using the java connector with a small client I have
> developed for testing.
> For the broadcast_rpc_address I have configured the local IP of
> the nodes. The cluster works fine and nodes communicates fairly
> well using their local IPs. When I connect to a node (let's say
> node 1) from the outside using the java driver and the node's
> public IP, the cluster discovery uses internal IPs for contacting
> other nodes, leading to (obviously) errors.
>
> As for AWS, Elastic IPs are free as long as they're associated to
> an instance and the machines are up 24h/7. I have to shut down the
> machines during the night for various reasons, so unfortunately
> they're not totally free for my use case.
>
>
>
> Il 05/10/2015 00:04, Jonathan Haddad ha scritto:
>> Public IP? No, not required unless you're running multiple DCs.
>>
>> Where are you running a DC that IPs aren't cheap? If you're in
>> AWS they're basically free (or at least the cheapest section of
>> your bill by far)
>>
>>
>>
>> On Sun, Oct 4, 2015 at 5:59 PM Renato Perini
>> <renato.perini@gmail.com <ma...@gmail.com>> wrote:
>>
>> Is cassandra really supposed to have a static public IP for
>> each and
>> single node in the cluster?
>> This seems to be expensive (static IPs are nor free neither
>> cheap),
>> still the broadcast_rpc_address expects a static IP for client
>> communications (load balancing, contact points, etc.)
>> Is there some mechanism to determine a public IP at runtime?
>>
>> Basically, I have nodes (machines) with dynamic public IPs
>> and I cannot
>> embed them in the cassandra.yaml file because of their
>> dynamic nature
>> (they change at each reboot).
>> Any solution to this?
>>
>> Thanks.
>>
>
Re: Cassandra Configuration VS Static IPs.
Posted by Jonathan Haddad <jo...@jonhaddad.com>.
So you're not running the client in the same DC as your Cassandra cluster.
In that case you'll need to be able to connect to the public address of all
the nodes. Technically you could have a whitelist and only connect to 1, I
wouldn't recommend it.
This is no different than any other database in that you would need a
public address to be able to connect to the servers from a machine not in
your datacenter. How else would you connect to them if you don't provide
access?
On Sun, Oct 4, 2015 at 6:35 PM Renato Perini <re...@gmail.com>
wrote:
> Seems to be not the case when connecting to my (single) data center using
> the java connector with a small client I have developed for testing.
> For the broadcast_rpc_address I have configured the local IP of the nodes.
> The cluster works fine and nodes communicates fairly well using their local
> IPs. When I connect to a node (let's say node 1) from the outside using the
> java driver and the node's public IP, the cluster discovery uses internal
> IPs for contacting other nodes, leading to (obviously) errors.
>
> As for AWS, Elastic IPs are free as long as they're associated to an
> instance and the machines are up 24h/7. I have to shut down the machines
> during the night for various reasons, so unfortunately they're not totally
> free for my use case.
>
>
>
> Il 05/10/2015 00:04, Jonathan Haddad ha scritto:
>
> Public IP? No, not required unless you're running multiple DCs.
>
> Where are you running a DC that IPs aren't cheap? If you're in AWS
> they're basically free (or at least the cheapest section of your bill by
> far)
>
>
>
> On Sun, Oct 4, 2015 at 5:59 PM Renato Perini <re...@gmail.com>
> wrote:
>
>> Is cassandra really supposed to have a static public IP for each and
>> single node in the cluster?
>> This seems to be expensive (static IPs are nor free neither cheap),
>> still the broadcast_rpc_address expects a static IP for client
>> communications (load balancing, contact points, etc.)
>> Is there some mechanism to determine a public IP at runtime?
>>
>> Basically, I have nodes (machines) with dynamic public IPs and I cannot
>> embed them in the cassandra.yaml file because of their dynamic nature
>> (they change at each reboot).
>> Any solution to this?
>>
>> Thanks.
>>
>
>
Re: Cassandra Configuration VS Static IPs.
Posted by Renato Perini <re...@gmail.com>.
Seems to be not the case when connecting to my (single) data center
using the java connector with a small client I have developed for testing.
For the broadcast_rpc_address I have configured the local IP of the
nodes. The cluster works fine and nodes communicates fairly well using
their local IPs. When I connect to a node (let's say node 1) from the
outside using the java driver and the node's public IP, the cluster
discovery uses internal IPs for contacting other nodes, leading to
(obviously) errors.
As for AWS, Elastic IPs are free as long as they're associated to an
instance and the machines are up 24h/7. I have to shut down the machines
during the night for various reasons, so unfortunately they're not
totally free for my use case.
Il 05/10/2015 00:04, Jonathan Haddad ha scritto:
> Public IP? No, not required unless you're running multiple DCs.
>
> Where are you running a DC that IPs aren't cheap? If you're in AWS
> they're basically free (or at least the cheapest section of your bill
> by far)
>
>
>
> On Sun, Oct 4, 2015 at 5:59 PM Renato Perini <renato.perini@gmail.com
> <ma...@gmail.com>> wrote:
>
> Is cassandra really supposed to have a static public IP for each and
> single node in the cluster?
> This seems to be expensive (static IPs are nor free neither cheap),
> still the broadcast_rpc_address expects a static IP for client
> communications (load balancing, contact points, etc.)
> Is there some mechanism to determine a public IP at runtime?
>
> Basically, I have nodes (machines) with dynamic public IPs and I
> cannot
> embed them in the cassandra.yaml file because of their dynamic nature
> (they change at each reboot).
> Any solution to this?
>
> Thanks.
>
Re: Cassandra Configuration VS Static IPs.
Posted by Jonathan Haddad <jo...@jonhaddad.com>.
Public IP? No, not required unless you're running multiple DCs.
Where are you running a DC that IPs aren't cheap? If you're in AWS they're
basically free (or at least the cheapest section of your bill by far)
On Sun, Oct 4, 2015 at 5:59 PM Renato Perini <re...@gmail.com>
wrote:
> Is cassandra really supposed to have a static public IP for each and
> single node in the cluster?
> This seems to be expensive (static IPs are nor free neither cheap),
> still the broadcast_rpc_address expects a static IP for client
> communications (load balancing, contact points, etc.)
> Is there some mechanism to determine a public IP at runtime?
>
> Basically, I have nodes (machines) with dynamic public IPs and I cannot
> embed them in the cassandra.yaml file because of their dynamic nature
> (they change at each reboot).
> Any solution to this?
>
> Thanks.
>