eglamkowski's Journal: what do you suppose this means?

What does it mean when I can successfully connect to server A via ftp from server B, but am unable to ping server A from server B.

But I can successfully ping server A from server C, as well as connect to it via ftp. I can also successfully ping server B from server C no problem.

There's no problem with ping on server B, since I can successfully ping server D from it, just not server A.

I'm so confused...

filter on the switch?

[RailGunner]

Some routers can be configured to eat certain types of messages. Ping traffic may be one...

I've seen routers set up to eat all UDP multi-cast or broadcast messages, for example. Kind of sucked when a UDP broadcast was a good way to find other nodes on the subnet..

Windows?

[Jeremiah Cornelius]

Local firewalls?

ICMP blocking through local firewall or IPSec policy?

Switch?

[Talinom]

Are they all in the same IP range? Is there a switch between server B and server A? Can you ping server A from anything else on the same switch?

Are there any IP filters along the way on either servers A or B? Make a logic table of what happens when you do this:
Ping A > A
Ping A > B
Ping A > C
Ping B > A
Ping B > B
Ping B > C
Ping C > A
Ping C > B
Ping C > C

Yeah, can A ping it's own IP address (or even localhost) or does it get filtered out? How does it look on a network di

Re:

[bofkentucky]

stating the obvious, but does resolv.conf reference the openbsd box?

Re:

[Talinom]

Nope. That was the first place I checked. resolv.conf currently contains:
nameserver 208.67.222.222
nameserver 208.67.220.220

When I manually put the ip and hostname into the hosts file I get the following output when running mythfilldatabase

2007-02-24 18:41:21.393 New DB connection, total: 1
2007-02-24 18:41:21.401 mythfilldatabase: Listings Download Started
2007-02-24 18:41:21.402 New DB connection, total: 2
Refreshing Tomorrow's data
2007-02-24 18:41:21.424 New DB DataDirect connection
Retrieving da

Re:

[bofkentucky]

glad I could help, but now I've got to clean my prod.

Possibley...

[FroMan]

Possibley the router between A and B is dropping everything (atleast icmp ping) between A and B. Why? That would depend. It could be that there is a firewall that has a hole punched only to allow ftp through, or tcp only.

Re:

[Degrees]

To make this point in a different way; FTP runs over TCP/IP, whereas ping is a part of a wholly different protocol: ICMP. It is reasonably easy to believe that a firewall might be configured to allow TCP (any flavor), and not allow ICMP.

I've also run into cases where the router in front of Server X could ping Server Z, but the router in front of Server Z could not ping Server X. Invariably this was a case of a mis-configured route table. The router in front of Server Z did not know where to send the packet