Bug 18332
| Summary: | internet programs leave too many connections open | ||
|---|---|---|---|
| Product: | [Retired] Red Hat Linux | Reporter: | Jaanus J6gisman <jaanus> |
| Component: | glibc | Assignee: | Jakub Jelinek <jakub> |
| Status: | CLOSED ERRATA | QA Contact: | |
| Severity: | medium | Docs Contact: | |
| Priority: | high | ||
| Version: | 7.0 | CC: | ckjohnson, dr, dro, john.eckerdal, noelmorgan, t8m |
| Target Milestone: | --- | ||
| Target Release: | --- | ||
| Hardware: | i386 | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | Bug Fix | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2001-01-11 12:47:17 UTC | Type: | --- |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
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Description
Jaanus J6gisman
2000-10-04 14:48:22 UTC
Same problem here: xinet binds to (atleast) 3 ports to domain-name servers present in resolv.conf (one for each server). Fixed by restarting xinetd. I think this occured when a remote host without a name assigned to the IP tried to connect to a service it not had access to (blocked via tcp-wrappers). I have not noticed the same problem with Apache (talk is not enabled). Apache is, however, not configured to do a reverse-name lookup. in my case apache was configured to perform hostname lookups. if i disabled it, then it was fine, but that't not solution. Reassigned to glibc is it possible to fix this problem? i hoped that the patch for glibc fixes it, but it didn't help. Sure, if I'll be able to reproduce it. So far I have enabled hostname lookups in Apache and could not see any excessive connections to nameservers. One open connection per nameserver is nothing bad if the application (see man gethostbyname), but the netstat output with those httpd connections does not look too healthy. Can you see it e.g. if no DNS server is running on the local machine (and all DNS lookups go to remote nameservers)? i disabled local nameserver, but it removed only connections to local nameserver... i think that these connection are left open, if an connection to some service (apache, xinetd, ...) is made from a machine which name can not be looked up. there were 3 dns servers in resolv.conf now i removed 2 remote ones and need to wait until some server without a name makes a connection... is it possible to close a connection without restarting a program that made this connection? This happened to me again. Had atleast 6 established connections to all nameservers in resolv.conf. Apache is not set to do reverse namelookups. xinetd does however do reverse namelookups. Restarting xinetd removes the established connections. The established connections only happen when xinetd can't resolve the connecting hostname. Here I have only seen this happen when the connecting host does not have a name in any DNS. Also calling nslookup to lookup the host does not leave any ports in established mode (even when nslookup is running). The system is running glibc-2.1.94-3 and a 2.2.17 kernel (not RedHat compiled). I've been able to reproduce this finally and fixed it recently in glibc. It will appear in the next glibc errata. *** Bug 23712 has been marked as a duplicate of this bug. *** I believe glibc-2.2-12 fixes this, if not, please reopen. *** Bug 24790 has been marked as a duplicate of this bug. *** |