Re: bind-address by name under 5.0.18
Hi James,
Sort of. If I run the command manually, it does.
But my script uses su to run the server as an unprivileged user.
What happens if you:
su -m mysql -c 'sh -c /usr/local/bin/mysqld_safe
--defaults-extra-file=/var/db/mysql/my.cnf --user=mysql --datadir=/var/db/mysql
--pid-file=/var/db/mysql/www.example.com.pid --bind-address=localhost /dev/null '
Hmm, I don't see why it shouldn't work when run inside su... odd.
As far as I know, there are no requirements for superuser in order to
bind to certain IPs.
I'm also hopeful to get multi-IP support, so that I can have the
server listen on two NICs or what-have-you, such as:
[mysqld]
bind_address=foo bar localhost
This is a reasonable feature request, and I'll try to do it (I don't see
why it can't work). It would require some changes to how the address to
bind to are passed around (currently a variable called my_bind_addr).
I haven't tried that yet, so perhaps it is already functional as
well, I'll try to get to testing that soon.
It's not. Here's the code that handles bind-address from sql/mysqld.cc:
6733case (int) OPT_BIND_ADDRESS:
6734 if ((my_bind_addr= (ulong) inet_addr(argument)) == INADDR_NONE)
6735 {
6736struct hostent *ent;
6737if (argument[0])
6738 ent=gethostbyname(argument);
6739else
6740{
6741 char myhostname[255];
6742 if (gethostname(myhostname,sizeof(myhostname)) 0)
6743 {
6744sql_perror(Can't start server: cannot get my own
hostname!);
6745exit(1);
6746 }
6747 ent=gethostbyname(myhostname);
6748}
6749if (!ent)
6750{
6751 sql_perror(Can't start server: cannot resolve hostname!);
6752 exit(1);
6753}
6754my_bind_addr = (ulong)
((in_addr*)ent-h_addr_list[0])-s_addr;
6755 }
6756 break;
And with other DBs, I can set 'sql.example.com' to resolve to N
IPs (N=4 in this example):
10.0.0.10
10.0.1.10
10.0.2.10
10.0.3.10
Then I can have N separate hosts share the same start-up script,
because the SQL server binds only to those IPs which are local. Since
each of the N servers has only one of those IPs locally, each
server automatically binds to the correct IP. And if the IPs ever
change, I just update DNS, and there's no need to do any maintenance
on the start-up scripts. These IPs would not necessarily be in the
same subnet and in fact, are CNAMEs, such as sql.example.com
defined as:
sql.example.com.IN CNAME dallas-sql.example.com
sql.example.com.IN CNAME cleveland-sql.example.com
sql.example.com.IN CNAME portland-sql.example.com
sql.example.com.IN CNAME sydney-sql.example.com
I am grateful to be making progress. Thank you for your assistance.
Hmm, I guess you'd expect to at least get warnings for each of these
that couldn't be bound to?
This seems like a very strange way to configure a machine. To each, his
own. :)
Regards,
Jeremy
--
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MySQL Geek, Yahoo! Inc.
Desk: 408 349 5104
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Re: bind-address by name under 5.0.18
6752 exit(1); 6753} 6754my_bind_addr = (ulong) ((in_addr*)ent-h_addr_list[0])-s_addr; 6755 } 6756 break; And with other DBs, I can set 'sql.example.com' to resolve to N IPs (N=4 in this example): 10.0.0.10 10.0.1.10 10.0.2.10 10.0.3.10 Then I can have N separate hosts share the same start-up script, because the SQL server binds only to those IPs which are local. Since each of the N servers has only one of those IPs locally, each server automatically binds to the correct IP. And if the IPs ever change, I just update DNS, and there's no need to do any maintenance on the start-up scripts. These IPs would not necessarily be in the same subnet and in fact, are CNAMEs, such as sql.example.com defined as: sql.example.com.IN CNAME dallas-sql.example.com sql.example.com.IN CNAME cleveland-sql.example.com sql.example.com.IN CNAME portland-sql.example.com sql.example.com.IN CNAME sydney-sql.example.com I am grateful to be making progress. Thank you for your assistance. Hmm, I guess you'd expect to at least get warnings for each of these that couldn't be bound to? A *warning*, yes. There's certainly no way to bind to an IP that isn't local. However, if the IP *is local*, and yet MySQL *still* can't bind to it, that should be an *error*. This seems like a very strange way to configure a machine. To each, his own. :) The advantage is that all the machines can have exactly the same configuration (except for the ifconfig IP). The sql start-up is exactly the same, and thus you only maintain 1 script instead of N. Another case where this would be handy is on a machine with multiple NICs on various LANs. One might set a DNS to resolve to the N different IPs that machine has, and then tell the SQL server to bind to that DNS name. The SQL server could then automatically answer queries on each of the IPs specified in DNS. Jim -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe:http://lists.mysql.com/[EMAIL PROTECTED]
Re: bind-address by name under 5.0.18
It doesn't allow to bind to a hostname. According to http://dev.mysql.com/doc/refman/5.0/en/server-options.html you have to specify an IP address, not a hostname. -Sheeri On 2/22/06, James Long [EMAIL PROTECTED] wrote: I would like to be able to bind to a host name, rather than an IP number. IP numbers come and go, and are beyond the control of anyone who doesn't have their own direct allocation. But since I own my domain, a host name is more permanent. When the time comes to change IP numbers, I want to just edit /etc/hosts to show my new IP: 10.0.0.10 shortname myrealname.example.com and use --bind-address=shortname in my start-up script to automatically pick up the new IP number. This eliminates the headache of having to find and fix umpteen literal IP numbers hiding in my startup scripts. This is much the same reason one says '#define BLKSIZ 512' and then uses the constant 'BLKSIZ' instead of sprinkling literal '512's throughout one's code). Why doesn't bind-address allow this? Or if it does, how can I accomplish this? Thanks! Jim -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe:http://lists.mysql.com/[EMAIL PROTECTED] -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe:http://lists.mysql.com/[EMAIL PROTECTED]
Re: bind-address by name under 5.0.18
It doesn't allow to bind to a hostname. According to http://dev.mysql.com/doc/refman/5.0/en/server-options.html you have to specify an IP address, not a hostname. -Sheeri Thanks for your reply. Yes, I am aware of that, as stated in my question. Wouldn't it be an improvement if it did, though? Currently, I have to use an ugly grep/awk hack to grep the address out of /etc/hosts. Are there technical reasons that make it difficult to write the code such that one could specify an IP or a hostname, or a list of IPs and/or hostnames? I'm looking for something similar to PostgreSQL's: -h hostname Specifies the IP host name or address on which the postmaster is to listen for TCP/IP connections from client applications. The value can also be a space-separated list of addresses, or * to specify listening on all available interfaces. An empty value specifies not listening on any IP addresses, in which case only Unix-domain sockets can be used to connect to the postmaster. Defaults to listening only on localhost. Specifying this option is equivalent to setting the listen_addresses configuration parameter. On 2/22/06, James Long [EMAIL PROTECTED] wrote: I would like to be able to bind to a host name, rather than an IP number. IP numbers come and go, and are beyond the control of anyone who doesn't have their own direct allocation. But since I own my domain, a host name is more permanent. When the time comes to change IP numbers, I want to just edit /etc/hosts to show my new IP: 10.0.0.10 shortname myrealname.example.com and use --bind-address=shortname in my start-up script to automatically pick up the new IP number. This eliminates the headache of having to find and fix umpteen literal IP numbers hiding in my startup scripts. This is much the same reason one says '#define BLKSIZ 512' and then uses the constant 'BLKSIZ' instead of sprinkling literal '512's throughout one's code). Why doesn't bind-address allow this? Or if it does, how can I accomplish this? Thanks! Jim -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe:http://lists.mysql.com/[EMAIL PROTECTED] -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe:http://lists.mysql.com/[EMAIL PROTECTED]
Re: bind-address by name under 5.0.18
Yes, there is a very good, not so technical reason to only allow binding by IP Address. Have you ever heard of putting the cart before the horse ? If binding by hostname were allowed, that would mean that every time your MySQL server started up, it would need to somehow resolve that name into an address. In order to do that, it needs a socket it can use to contact a DNS server in order to change the hostname back into an address. Where does it get the socket? Without a socket, it cannot contact a DNS server so it cannot resolve it's hostname to an address and it will not be able to bind to a socket. Binding is the process of giving a socket (an address and a port) to an application so that it has a point of contact on the internet. Without a socket an application has no way to communicate over TCP/IP or UDP/IP as there would be nowhere for the return messages to land. That is the simple reason why you cannot bind to a hostname. Did I make sense? Shawn Green Database Administrator Unimin Corporation - Spruce Pine James Long [EMAIL PROTECTED] wrote on 02/27/2006 03:59:14 PM: It doesn't allow to bind to a hostname. According to http://dev.mysql.com/doc/refman/5.0/en/server-options.html you have to specify an IP address, not a hostname. -Sheeri Thanks for your reply. Yes, I am aware of that, as stated in my question. Wouldn't it be an improvement if it did, though? Currently, I have to use an ugly grep/awk hack to grep the address out of /etc/hosts. Are there technical reasons that make it difficult to write the code such that one could specify an IP or a hostname, or a list of IPs and/or hostnames? I'm looking for something similar to PostgreSQL's: -h hostname Specifies the IP host name or address on which the postmaster is to listen for TCP/IP connections from client applications. The value can also be a space-separated list of addresses, or * to specify listening on all available interfaces. An empty value specifies not listening on any IP addresses, in which case only Unix-domain sockets can be used to connect to the postmaster. Defaults to listening only on localhost. Specifying this option is equivalent to setting the listen_addresses configuration parameter. On 2/22/06, James Long [EMAIL PROTECTED] wrote: I would like to be able to bind to a host name, rather than an IP number. IP numbers come and go, and are beyond the control of anyone who doesn't have their own direct allocation. But since I own my domain, a host name is more permanent. When the time comes to change IP numbers, I want to just edit /etc/hosts to show my new IP: 10.0.0.10 shortname myrealname.example.com and use --bind-address=shortname in my start-up script to automatically pick up the new IP number. This eliminates the headache of having to find and fix umpteen literal IP numbers hiding in my startup scripts. This is much the same reason one says '#define BLKSIZ 512' and then uses the constant 'BLKSIZ' instead of sprinkling literal '512's throughout one's code). Why doesn't bind-address allow this? Or if it does, how can I accomplish this? Thanks! Jim -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED] -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe:http://lists.mysql.com/[EMAIL PROTECTED]
Re: bind-address by name under 5.0.18
You seem to be unaware of /etc/hosts. Yes, there is a very good, not so technical reason to only allow binding by IP Address. Have you ever heard of putting the cart before the horse ? If binding by hostname were allowed, that would mean that every time your MySQL server started up, it would need to somehow resolve that name into an address. In order to do that, it needs a socket it can use to contact a DNS server in order to change the hostname back into an address. Where does it get the socket? Without a socket, it cannot contact a DNS server so it cannot resolve it's hostname to an address and it will not be able to bind to a socket. I can't speak for your machine, but on my servers, DNS is up before MySQL starts. Binding is the process of giving a socket (an address and a port) to an application so that it has a point of contact on the internet. Without a socket an application has no way to communicate over TCP/IP or UDP/IP as there would be nowhere for the return messages to land. That is the simple reason why you cannot bind to a hostname. Did I make sense? Yes, but none of the information was new. Shawn Green Database Administrator Unimin Corporation - Spruce Pine James Long [EMAIL PROTECTED] wrote on 02/27/2006 03:59:14 PM: It doesn't allow to bind to a hostname. According to http://dev.mysql.com/doc/refman/5.0/en/server-options.html you have to specify an IP address, not a hostname. -Sheeri Thanks for your reply. Yes, I am aware of that, as stated in my question. Wouldn't it be an improvement if it did, though? Currently, I have to use an ugly grep/awk hack to grep the address out of /etc/hosts. Are there technical reasons that make it difficult to write the code such that one could specify an IP or a hostname, or a list of IPs and/or hostnames? I'm looking for something similar to PostgreSQL's: -h hostname Specifies the IP host name or address on which the postmaster is to listen for TCP/IP connections from client applications. The value can also be a space-separated list of addresses, or * to specify listening on all available interfaces. An empty value specifies not listening on any IP addresses, in which case only Unix-domain sockets can be used to connect to the postmaster. Defaults to listening only on localhost. Specifying this option is equivalent to setting the listen_addresses configuration parameter. On 2/22/06, James Long [EMAIL PROTECTED] wrote: I would like to be able to bind to a host name, rather than an IP number. IP numbers come and go, and are beyond the control of anyone who doesn't have their own direct allocation. But since I own my domain, a host name is more permanent. When the time comes to change IP numbers, I want to just edit /etc/hosts to show my new IP: 10.0.0.10 shortname myrealname.example.com and use --bind-address=shortname in my start-up script to automatically pick up the new IP number. This eliminates the headache of having to find and fix umpteen literal IP numbers hiding in my startup scripts. This is much the same reason one says '#define BLKSIZ 512' and then uses the constant 'BLKSIZ' instead of sprinkling literal '512's throughout one's code). Why doesn't bind-address allow this? Or if it does, how can I accomplish this? Thanks! Jim -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED] -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe:http://lists.mysql.com/[EMAIL PROTECTED] --=_alternative 0075136A85257122_= Content-Type: text/html; charset=US-ASCII brfont size=2 face=sans-serifYes, there is a very good, not so technical reason to only allow binding by IP Address. nbsp;Have you ever heard of quot;putting the cart before the horsequot; ?/font br brfont size=2 face=sans-serifIf binding by hostname were allowed, that would mean that every time your MySQL server started up, it would need to somehow resolve that name into an address. In order to do that, it needs a socket it can use to contact a DNS server in order to change the hostname back into an address. Where does it get the socket? Without a socket, it cannot contact a DNS server so it cannot resolve it's hostname to an address and it will not be able to bind to a socket./font br brfont size=2 face=sans-serifBinding is the process of giving a socket (an address and a port) to an application so that it has a point of contact on the internet. Without a socket an application has no way to communicate over TCP/IP or UDP/IP as there would be nowhere for the return messages to land. That is the simple reason why you
Re: bind-address by name under 5.0.18
Oh, no. I know about etc/hosts (even Windoze boxes has one). It's just normally not available for reference until you bind your socket library to at least one socket. Again, it's a cart and horse thing. You see, the etc/hosts file counts as a local DNS server and the DNS protocol requires a socket ( I am not aware of any IP stack that will allow an etc/hosts lookup until you have at least one socket established (though I could be wrong). Shawn Green Database Administrator Unimin Corporation - Spruce Pine James Long [EMAIL PROTECTED] wrote on 02/27/2006 04:26:37 PM: You seem to be unaware of /etc/hosts. Yes, there is a very good, not so technical reason to only allow binding by IP Address. Have you ever heard of putting the cart before the horse ? If binding by hostname were allowed, that would mean that every time your MySQL server started up, it would need to somehow resolve that name into an address. In order to do that, it needs a socket it can use to contact a DNS server in order to change the hostname back into an address. Where does it get the socket? Without a socket, it cannot contact a DNS server so it cannot resolve it's hostname to an address and it will not be able to bind to a socket. I can't speak for your machine, but on my servers, DNS is up before MySQL starts. Binding is the process of giving a socket (an address and a port) to an application so that it has a point of contact on the internet. Without a socket an application has no way to communicate over TCP/IP or UDP/IP as there would be nowhere for the return messages to land. That is the simple reason why you cannot bind to a hostname. Did I make sense? Yes, but none of the information was new. Shawn Green Database Administrator Unimin Corporation - Spruce Pine James Long [EMAIL PROTECTED] wrote on 02/27/2006 03:59:14 PM: It doesn't allow to bind to a hostname. According to http://dev.mysql.com/doc/refman/5.0/en/server-options.html you have to specify an IP address, not a hostname. -Sheeri Thanks for your reply. Yes, I am aware of that, as stated in my question. Wouldn't it be an improvement if it did, though? Currently, I have to use an ugly grep/awk hack to grep the address out of /etc/hosts. Are there technical reasons that make it difficult to write the code such that one could specify an IP or a hostname, or a list of IPs and/or hostnames? I'm looking for something similar to PostgreSQL's: -h hostname Specifies the IP host name or address on which the postmaster is to listen for TCP/IP connections from client applications. The value can also be a space-separated list of addresses, or * to specify listening on all available interfaces. An empty value specifies not listening on any IP addresses, in which case only Unix-domain sockets can be used to connect to the postmaster. Defaults to listening only on localhost. Specifying this option is equivalent to setting the listen_addresses configuration parameter. On 2/22/06, James Long [EMAIL PROTECTED] wrote: I would like to be able to bind to a host name, rather than an IP number. IP numbers come and go, and are beyond the control of anyone who doesn't have their own direct allocation. But since I own my domain, a host name is more permanent. When the time comes to change IP numbers, I want to just edit /etc/hosts to show my new IP: 10.0.0.10 shortname myrealname.example.com and use --bind-address=shortname in my start-up script to automatically pick up the new IP number. This eliminates the headache of having to find and fix umpteen literal IP numbers hiding in my startup scripts. This is much the same reason one says '#define BLKSIZ 512' and then uses the constant 'BLKSIZ' instead of sprinkling literal '512's throughout one's code). Why doesn't bind-address allow this? Or if it does, how can I accomplish this? Thanks! Jim -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED] -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED] --=_alternative 0075136A85257122_= Content-Type: text/html; charset=US-ASCII brfont size=2 face=sans-serifYes, there is a very good, not so technical reason to only allow binding by IP Address. nbsp;Have you ever heard of quot;putting the cart before the horsequot; ?/font br brfont size=2 face=sans-serifIf binding by hostname were allowed, that would mean that every time your MySQL server started up,
Re: bind-address by name under 5.0.18
Oh, no. I know about etc/hosts (even Windoze boxes has one). It's just normally not available for reference until you bind your socket library to at least one socket. Again, it's a cart and horse thing. You see, the etc/hosts file counts as a local DNS server and the DNS protocol requires a socket ( But an *outgoing* socket for DNS lookups is different from the listening address the server binds to. I am not aware of any IP stack that will allow an etc/hosts lookup until you have at least one socket established (though I could be wrong). Look, with all due respect to your experience, I can assure you that none of this is rocket science, nor is it a chicken-and-egg sort of problem. It's not impossible to do. Other databases do it. IANASE, but I should think a simple call to gethostbyname(3) should do the trick: The structure returned contains either the information obtained from the name server, named(8), broken-out fields from a line in /etc/hosts, or database entries supplied by the yp(8) system. The order of the lookups is controlled by the `hosts' entry in nsswitch.conf(5). PostgreSQL's -h option is an example of the functionality I'm trying to find in MySQL, as I posted in an earlier message (on which you were not yet cc'ed, and which may not have hit the list yet). It allows the administrator to specify a *list* of IPs *OR* hostnames that the database server should bind to for incoming client connections: -h hostname Specifies the IP host name or address on which the postmaster is to listen for TCP/IP connections from client applications. The value can also be a space-separated list of addresses, or * to specify listening on all available interfaces. An empty value specifies not listening on any IP addresses, in which case only Unix-domain sockets can be used to connect to the postmaster. Defaults to listening only on localhost. Specifying this option is equivalent to setting the listen_addresses configuration parameter. So I could start Postgres with -h localhost priv pub sql.example.com and bind to those IPs. Further, if those DNS names resolve to multiple IPs, then Postgres will bind to as many of them as it can find on the local machine. How do I do that with MySQL? Thanks again for taking the time to answer my questions. Jim -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe:http://lists.mysql.com/[EMAIL PROTECTED]
Re: bind-address by name under 5.0.18
Hi James, I would like to be able to bind to a host name, rather than an IP number. IP numbers come and go, and are beyond the control of anyone who doesn't have their own direct allocation. But since I own my domain, a host name is more permanent. Adding this functionality is fairly trivial, with the caveat that it will have to use the first address returned by gethostbyname(), so if you have multiple IPs assigned to a hostname (for e.g. round-robin DNS) it will be interesting. :) This is probably a 5-10 line patch, including error checking. Regards, Jeremy -- Jeremy Cole MySQL Geek, Yahoo! Inc. Desk: 408 349 5104 -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe:http://lists.mysql.com/[EMAIL PROTECTED]
Re: bind-address by name under 5.0.18
Hi James, I would like to be able to bind to a host name, rather than an IP number. IP numbers come and go, and are beyond the control of anyone who doesn't have their own direct allocation. But since I own my domain, a host name is more permanent. Adding this functionality is fairly trivial, with the caveat that it will have to use the first address returned by gethostbyname(), so if you have multiple IPs assigned to a hostname (for e.g. round-robin DNS) it will be interesting. :) Thanks for your reply. Just for my edification, how come only one IP? Add another 10 lines and you should be able to make it bind to all IPs returned. Currently bind-address supports only one IP to bind to. This is a reasonable request, I'll take a crack at it. Regards, Jeremy Thank you very much! I'm willing to help test if you can provide me a diff of your changes. Jim -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe:http://lists.mysql.com/[EMAIL PROTECTED]
Re: bind-address by name under 5.0.18
Hi, Thank you very much! I'm willing to help test if you can provide me a diff of your changes. Well, that was easy. I checked the code, and it turns out that the functionality is already there. I just tested it on my laptop (running 5.0.13) and it does indeed work. I did: * echo 10.0.0.1 foo /etc/hosts * ifconfig lo0 alias 10.0.0.1 * add to /etc/my.cnf: [mysqld] bind-address=foo * restart mysqld * mysql -h 10.0.0.1 -- confirm connection or error from mysqld * mysql -h 127.0.0.1 -- confirm failure to connect at all I didn't know that this worked. Learn something new every day. Are you having a problem with it? Does it not work for you? Regards, Jeremy -- Jeremy Cole MySQL Geek, Yahoo! Inc. Desk: 408 349 5104 -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe:http://lists.mysql.com/[EMAIL PROTECTED]
Re: bind-address by name under 5.0.18
Hi, Thank you very much! I'm willing to help test if you can provide me a diff of your changes. Well, that was easy. I checked the code, and it turns out that the functionality is already there. I just tested it on my laptop (running 5.0.13) and it does indeed work. I did: * echo 10.0.0.1 foo /etc/hosts * ifconfig lo0 alias 10.0.0.1 * add to /etc/my.cnf: [mysqld] bind-address=foo * restart mysqld * mysql -h 10.0.0.1 -- confirm connection or error from mysqld * mysql -h 127.0.0.1 -- confirm failure to connect at all I didn't know that this worked. Learn something new every day. Are you having a problem with it? Does it not work for you? Sort of. If I run the command manually, it does. But my script uses su to run the server as an unprivileged user. What happens if you: su -m mysql -c 'sh -c /usr/local/bin/mysqld_safe --defaults-extra-file=/var/db/mysql/my.cnf --user=mysql --datadir=/var/db/mysql --pid-file=/var/db/mysql/www.example.com.pid --bind-address=localhost /dev/null ' I'm also hopeful to get multi-IP support, so that I can have the server listen on two NICs or what-have-you, such as: [mysqld] bind_address=foo bar localhost I haven't tried that yet, so perhaps it is already functional as well, I'll try to get to testing that soon. And with other DBs, I can set 'sql.example.com' to resolve to N IPs (N=4 in this example): 10.0.0.10 10.0.1.10 10.0.2.10 10.0.3.10 Then I can have N separate hosts share the same start-up script, because the SQL server binds only to those IPs which are local. Since each of the N servers has only one of those IPs locally, each server automatically binds to the correct IP. And if the IPs ever change, I just update DNS, and there's no need to do any maintenance on the start-up scripts. These IPs would not necessarily be in the same subnet and in fact, are CNAMEs, such as sql.example.com defined as: sql.example.com.IN CNAME dallas-sql.example.com sql.example.com.IN CNAME cleveland-sql.example.com sql.example.com.IN CNAME portland-sql.example.com sql.example.com.IN CNAME sydney-sql.example.com I am grateful to be making progress. Thank you for your assistance. Jim -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe:http://lists.mysql.com/[EMAIL PROTECTED]
