[OpenAFS] OpenAFS with RAID

[Chaskiel M Grundman]

--==========675AE0EC9A4085A540C9==========
Content-Type: text/plain; charset=us-ascii; format=flowed
Content-Transfer-Encoding: quoted-printable
Content-Disposition: inline

--On Wednesday, December 28, 2005 03:39:34 PM +0000 Paul Robins=20
<paul@paulrobins.alldaypa.com> wrote:

> If either of you could weigh in on AFS on top of DRBD i'd appreciate it,
> I'm not fully up on whether a second server with an identical filesystem
> could be made to take over a crashed AFS machine.

There are a couple of issues

1) would DRBD actually notice that the storage device on the primary node=20
is "hanging" and switch over to the secondary? I didn't think that most=20
heartbeat services would catch this
2) there would be a significant delay bringing up the secondary node as a=20
fileserver: Since the volumes were likely to all be "attached" (in use) by=20
the primary node's fileserver at the time of the failover, the DRBD=20
partition would need to be salvaged (a secondary fsck of the afs metadata)=20
before the fileserver could be started on the secondary machine.
3) you would need to do some sort of IP address takeover in order for=20
clients to contact the correct machine to get at the data. (The AFS=20
architecture provides better ways to do this, but the tools for using them=20
in a case like this aren't there at the moment)
--==========675AE0EC9A4085A540C9==========
Content-Type: application/pkcs7-signature
Content-Transfer-Encoding: base64

MIIFYwYJKoZIhvcNAQcCoIIFVDCCBVACAQExCzAJBgUrDgMCGgUAMAsGCSqGSIb3
DQEHAaCCAucwggLjMIICTKADAgECAgMO/8kwDQYJKoZIhvcNAQEEBQAwYjELMAkG
A1UEBhMCWkExJTAjBgNVBAoTHFRoYXd0ZSBDb25zdWx0aW5nIChQdHkpIEx0ZC4x
LDAqBgNVBAMTI1RoYXd0ZSBQZXJzb25hbCBGcmVlbWFpbCBJc3N1aW5nIENBMB4X
DTA1MDYyMzE3MzEzMFoXDTA2MDYyMzE3MzEzMFowRTEfMB0GA1UEAxMWVGhhd3Rl
IEZyZWVtYWlsIE1lbWJlcjEiMCAGCSqGSIb3DQEJARYTY2cydkBhbmRyZXcuY211
LmVkdTCCASIwDQYJKoZIhvcNAQEBBQADggEPADCCAQoCggEBALujtch96NHbplBs
5DnSTn03EsnbYsLng/wM+wbfyS6ml6CCGYl7HY+sIBm4DNygpyQz0mvtvy9kKz7V
M2GTYdH5QLOgxxPxzV3fItv4jF9LKr9tIiT+v9K7XQ2Xl4kDyJi1g19UsKU4wf+s
uFdennXZ0pkWTpUld9JRZiLSYQDs/Hi62OekBfIX+H96AskyMBhZj5OVA+CYtnCj
fzVYO4a/RoAmemQhlv+whF0Qa3QFrLZtrDXKeYX95KU78q6+cJqtiAri4H3k8NpD
SeWavUxFyH/PFhCYPVdfVDiwaTwfEI5lBF0vTTTL8kSnJSmRBRWw9RkYHNZ8hxBC
Oo9m1oMCAwEAAaNAMD4wDgYDVR0PAQH/BAQDAgXgMB4GA1UdEQQXMBWBE2NnMnZA
YW5kcmV3LmNtdS5lZHUwDAYDVR0TAQH/BAIwADANBgkqhkiG9w0BAQQFAAOBgQCR
W9k/ckGNAJQ+DeUey0Hed2nlQb4goaakkHviC70vAVt0N34yrk3uxBf5Kch2olqM
SMCR+9+b1iXn0NU9n7QppayQ7SsYci3m8eMlaBk1pK91LrHGQL+ZEqOPqwhRmb0a
lQFAAoJpJdotCBzy0X1GP83i+2DUdT6ydPlmtsm8djGCAkQwggJAAgEBMGkwYjEL
MAkGA1UEBhMCWkExJTAjBgNVBAoTHFRoYXd0ZSBDb25zdWx0aW5nIChQdHkpIEx0
ZC4xLDAqBgNVBAMTI1RoYXd0ZSBQZXJzb25hbCBGcmVlbWFpbCBJc3N1aW5nIENB
AgMO/8kwCQYFKw4DAhoFAKCBsTAYBgkqhkiG9w0BCQMxCwYJKoZIhvcNAQcBMBwG
CSqGSIb3DQEJBTEPFw0wNTEyMjgxNTU5MDhaMCMGCSqGSIb3DQEJBDEWBBTQ06/f
dwBqdoIhPJVj2FjVGkRnKDBSBgkqhkiG9w0BCQ8xRTBDMAoGCCqGSIb3DQMHMA4G
CCqGSIb3DQMCAgIAgDANBggqhkiG9w0DAgIBQDAHBgUrDgMCBzANBggqhkiG9w0D
AgIBKDANBgkqhkiG9w0BAQEFAASCAQCBrN5vfJFTKl6I2dUEUMWthQj5Ej5Og2HM
+9qUpP4OqMZ8gJczm1qvAK0E1O3daNcxBHPtn6ouwkF/eM+GHtG6KfV2fg1rStue
pKkIuTuJjqNF4eKfRfrJ1H6bYfA4uMOpBI0g2Az8Jrfryjvd3/l1/K7eqFxTVBa9
97N/epzO3w1PAEHfvsgDLnVNPcaIkSNiAaUgCveACdADKlVrW0SFZO+8lTVDdfvf
STxWJ13CX75OUw5U1hC+/j4IR/uYNpIcZzR+qcxUJ9NHOUdPcw2zt7Wg8Jyj78B7
cWYfhdhTW3y8hW4y8jVgmKKX21suSFcEXpJxMUuTyEbh0zSv38CH

--==========675AE0EC9A4085A540C9==========--