Bug 170884
| Summary: | MTU of ethernet card can't be set before interface is up | ||||||
|---|---|---|---|---|---|---|---|
| Product: | [Fedora] Fedora | Reporter: | Sven Neuhaus <sven-redhat> | ||||
| Component: | initscripts | Assignee: | Bill Nottingham <notting> | ||||
| Status: | CLOSED WONTFIX | QA Contact: | Brock Organ <borgan> | ||||
| Severity: | medium | Docs Contact: | |||||
| Priority: | medium | ||||||
| Version: | 4 | CC: | denis, jgarzik, linville, rvokal | ||||
| Target Milestone: | --- | ||||||
| Target Release: | --- | ||||||
| Hardware: | All | ||||||
| OS: | Linux | ||||||
| Whiteboard: | |||||||
| Fixed In Version: | Doc Type: | Bug Fix | |||||
| Doc Text: | Story Points: | --- | |||||
| Clone Of: | Environment: | ||||||
| Last Closed: | 2006-08-07 18:24:46 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: | |||||||
| Bug Depends On: | |||||||
| Bug Blocks: | 124226 | ||||||
| Attachments: |
|
||||||
Created attachment 120007 [details]
moves the MTU section further back
this patch moves the "ip link set dev ${DEVICE} mtu ${MTU}"
behind the "ip link set dev ${REALDEVICE} up"
which fixes the problem for me.
This bug would have been detected much sooner if the feature from bug 124226 (RFE: set MTU from system-config-network) had been implemented. Do you see any problems with my patch? Theoretically, it might need a second stanza to handle DHCP, although I'd hope that nothing needs MTU set to actually *get* a IP address. I'm still curious is the 'inability to set MTU unless link is set up' is something that's specific to a particular driver, or is defined behavior - John/Jeff? I don't see anything to suggest that this is a generic problem. The sk98lin driver looks like it might be enforcing such a requirement, but I don't know why. Since this is FC4, I would suggest using the skge driver instead of sk98lin if at all possible. In most cases I have met MTU can be changed while interface is down. Closing this - this is best solved by fixing the driver to allow setting the MTU in all cases. |
From Bugzilla Helper: User-Agent: Mozilla/5.0 (X11; U; Linux i686; de-DE; rv:1.7.12) Gecko/20050922 Fedora/1.0.7-1.1.fc4 Firefox/1.0.7 Description of problem: In /etc/sysconfig/network-scripts/ifup-eth if the MTU parameter is configured in /etc/sysconfig/network-scripts/ifcfg-eth0 it will try to set the MTU with "ip link set dev ${DEVICE} mtu ${MTU}" before the interface is up. This fails with my Marvell GigE card (sk98lin driver, kernel 2.6.13-1.1526_FC4). Version-Release number of selected component (if applicable): initscripts-8.11.1 How reproducible: Always Steps to Reproduce: 1. Add non-standard MTU to /etc/sysconfig/network-scripts/ifcfg-eth0 2. make sure eth0 currently has the standard MTU: ifconfig eth0 mtu 1500 3. cd /etc/sysconfig/network-scripts; ./ifdown eth0; echo down; ./ifup eth0; echo up; ifconfig eth0 | grep MTU Actual Results: I see this output: down SIOCSIFMTU: Invalid argument up UP BROADCAST MULTICAST MTU:1500 Metric:1 Expected Results: This should have been the output if the MTU had been set without a problem: down up UP BROADCAST MULTICAST MTU:9000 Metric:1 Additional info: The fix (for me) is to move the section that sets the MTU behind the lines that set the interface to status "up".