最好在依赖网络的代码中使用IP地址或主机名？

Question

If you are programming an application which is heavily using the network (eg pings, dns resolves, etc), is it better to use IP addresses in the code (eg if making a folder path on a server - //192.183.181.182/test/test1 for example), or hostnames?

I am assuming IP addresses as they tend to be static in the enterprise, and hostnames can have aliases etc to a single IP address. Is this a valid reason to prefer IP addresses?

Thanks

Answer 1

使用硬编码IP地址的问题是，如果您需要更改它，您需要更改代码，而如果您使用主机名，如果您需要更改它，您可以更改主机名指向的位置，而无需触及代码:)

Answer 2

Fully agreeing with jcarlosn above, and throwing in my $0.02 as a network infrastructure guy...

As a network engineer, I could go on for quite some time about the number of instances where I've seen people mistakenly hard-code an IP into an application, and the suffering that happens for years because the company has to contort the growth of IT infrastructure around that original assumption of a hardcoded ip and a subnet in some particular facility. This has an impact on operational and capital expenses of the company.

Also consider what happens when that app is deployed on hundreds of PCs, and has now become business critical to your company and business partners.

Please use DNS names, or if you feel you must use an ip for some bizarre reason... use a local application config file as suggested in another post. Please understand though that a config file doesn't change the corporate downtime for a business-critical app to get migrated to a new IP address. If your desktop people are good, they can probably rewrite an application config file as quickly as you could migrate a DNS name... if you work for a company with no real scripting skills in the desktop deployment dept, please reconsider using DNS with no longer than a 30 minute TTL on that A record.

Answer 3

There are valid reasons for both. Multi-homed servers can cause issues when using names (as you mention), but IP addresses aren't necessarily stable either- especially in a DHCP environment that's not using reservations (more common than you might think).

If it were me, I'd put the path/hostname/IP in config- then you can change to whatever's needed without rebuilding the code. If you're doing name lookups yourself internally, just make sure your code is prepared for either an IP or a hostname.

Answer 4

IPv4 addresses (32bit addresses) are supposed to become obsolete in 2012, (I think they made a movie about that, with earthquakes and tsunamis.)

There are already no new IPv4 addresses available for sale.

The new standard, IPv6, uses.much longer addresses.

Let the user decide, if he/she has a hostname, store that. However, hostname may have more than 1 IP address.

If user provides an IP address (v4 or v6), store that.

If you get q MAC address, store that.

Explain the users pros and cons (eg names ate more static).