Bug 1462955
Summary: | [3.4] Node lost connectivity to pod on another node (due to invalid ARP cache) | ||
---|---|---|---|
Product: | OpenShift Container Platform | Reporter: | Ben Bennett <bbennett> |
Component: | Networking | Assignee: | Ben Bennett <bbennett> |
Status: | CLOSED ERRATA | QA Contact: | Meng Bo <bmeng> |
Severity: | urgent | Docs Contact: | |
Priority: | urgent | ||
Version: | 3.4.1 | CC: | aos-bugs, bmeng, dyocum, eparis, erjones, hongli, nraghava, pdwyer, rromerom, sgaikwad, stwalter |
Target Milestone: | --- | Keywords: | OpsBlocker |
Target Release: | 3.4.z | ||
Hardware: | Unspecified | ||
OS: | Linux | ||
Whiteboard: | |||
Fixed In Version: | Doc Type: | Bug Fix | |
Doc Text: |
Cause: When an IP address was re-used it would be generated with a random MAC address that would be different from the previous one.
Consequence: Any node with an ARP cache that still held the old entry for the IP would not be able to communicate with the node.
Fix: Generate the MAC address deterministically from the IP address.
Result: A re-used IP address will always have the same MAC address, so the ARP cache can not be out of sync. So the traffic will flow.
|
Story Points: | --- |
Clone Of: | 1451854 | Environment: | |
Last Closed: | 2017-07-11 10:47:38 UTC | Type: | Bug |
Regression: | --- | Mount Type: | --- |
Documentation: | --- | CRM: | |
Verified Versions: | Category: | --- | |
oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
Cloudforms Team: | --- | Target Upstream Version: | |
Embargoed: | |||
Bug Depends On: | 1451854 | ||
Bug Blocks: | 1462952 |
Comment 2
Ben Bennett
2017-06-21 15:53:46 UTC
verified in atomic-openshift-3.4.1.42-1.git.0.e775fe2.el7.x86_64 and the MAC address generation has been changed, and on other issue found during regression. >ip address 3: eth0@if15: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 8951 qdisc noqueue state UP link/ether 0a:58:0a:02:04:06 brd ff:ff:ff:ff:ff:ff link-netnsid 0 inet 10.2.4.6/23 scope global eth0 >openflow cookie=0x0, duration=8833.941s, table=2, n_packets=1, n_bytes=42, priority=100,arp,in_port=7,arp_spa=10.2.4.6,arp_sha=0a:58:0a:02:04:06 actions=load:0->NXM_NX_REG0[],goto_table:5 Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory, and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. https://access.redhat.com/errata/RHBA-2017:1640 |