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I can't ping a Mac server at port 8080 from a CentOS machine, but I can ping that Mac server from any other machine, so the port is definitely open. Where should I start looking for the issue? Totally stuck.

[~/www@centos]# curl IP_ADDRESS_OF_MAC_SERVER:8080

That just hangs. Any other curl attempt, like for Google, works just fine.

Any thoughts? Thanks!


traceroute gave me this:

Cannot handle "host" cmdline arg `IP_ADDRESS_OF_MAC_SERVER:8080' on position 1 (argc 1)

ping gave me an unknown host, and telnet's not installed.

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migrated from Feb 25 '14 at 4:08

This question came from our site for system and network administrators.

curl isn't ping. You should start by testing basic network connectivity by actually using ping (ICMP), as well as traceroute. From there you should be able to see if there is something blocking traffic between the CentOS machine and the MAC server. If those tests work, then it's likely there is a firewall that is blocking specifically port 8080 between those two servers. – blacklight Feb 25 '14 at 2:42
What do you get with # telnet IP_ADDRESS 8080 – mangia Feb 25 '14 at 2:45
See updated answer! – emm Feb 25 '14 at 3:40
What does it mean to "ping a Mac server at port 8080"? And why are you trying to traceroute to an IP and port? Honestly, it sounds like you are messing with tools you have no idea how to use. – David Schwartz Feb 25 '14 at 4:18
AFAIK, traceroute doesn't support port numbers. Use tracepath instead. Note that tracepath use the idiosyncratic syntax of address/port instead of address:port' – pepoluan Feb 25 '14 at 5:07

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