-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 On 8/29/14 10:05 PM, Madhusudan Ramanna wrote: > > I thought Varnish 4.0.1 has support for IMS. But looks like > varnish is not sending the IMS header to the backend. Or I'm > missing something. > > * << Request >> 32820 - ReqHeader User-Agent: curl/7.24.0 > (x86_64-apple-darwin12.0) libcurl/7.24.0 OpenSSL/0.9.8y zlib/1.2.5 > - ReqHeader Host: <<host>> - ReqHeader Accept: */* - > ReqHeader If-Modified-Since: Sat, 05 Oct 2013 10:19:56 GMT - > ReqHeader X-Forwarded-For: <<ip>> > > - BereqHeader User-Agent: curl/7.24.0 > (x86_64-apple-darwin12.0) libcurl/7.24.0 OpenSSL/0.9.8y zlib/1.2.5 > - BereqHeader Host: <<host>> - BereqHeader Accept: */* - > BereqHeader X-Forwarded-For: <<ip>> - BereqHeader > Accept-Encoding: gzip - BereqHeader X-Varnish: 65570
You have IMS in the client request, which Varnish has handled for some time. If Varnish finds a cache hit, and the object in cache has a Last-Modified header, then Varnish will respond accordingly (no backend request necessary). That's not new in version 4. What's new is that Varnish will add IMS to backend requests to refresh objects from its cache with expired TTL, for those objects that have a Last-Modified header, and if the keep timer has not expired. What you're missing is that you apparently expected the IMS header in the client request to be forwarded to the backend request. But Varnish won't do that for a cache miss -- the response might be cacheable, in which case we'll want the whole thing. Once you have the response in cache, then it can be refreshed via IMS. Best, Geoff - -- UPLEX Systemoptimierung Scheffelstraße 32 22301 Hamburg http://uplex.de/ Mob: +49-176-63690917 -----BEGIN PGP SIGNATURE----- Version: GnuPG/MacGPG2 v2.0.14 (Darwin) iQIcBAEBCAAGBQJUAY1kAAoJEOUwvh9pJNURoNcP/1N7NBZxpySWVnpY0Bzew1gb uXIuaxL/YDIE1kGVMB6XeHX0ChDCehswMRgdQKMmNjQhQfrXIRnwJT83s4NX3cIf y8j2IjrjSEaniQS9K1uhPs1HlCg+6M7Xsz/wfaRokhsVZTXNmQo9jcSAYJHkfUjo nLO27VGObO7lknCcHPObMj77XLs5EgMxyaVk5TOvYkakLQ5cLJbVaUmz/GR5fqU7 A8uHQms9xYsxiffinTxC2WkKL7n/T3VBvZ/KavFje/CoXt66+Ggc9rc/pBbBY9SJ 8BYzOrJVYDvXL8EiNhpEk/DJHdGrmbANX7S/rihAXoDuRZKihRfDSzJrT7d1/949 KtoOXbns45PxXvDkDaU7lPTFfwVjxE5yC3ewDCXlmzTKd+KsOmov85yylJNpw29T 7WPTAHIsm14Y/BKRhNOUtjNzrg51dDvVS/IQHo3t+M0T2VJrTkWWEf3oWtYWTpJ2 wuBKdHZD5j4x0KSbvd4sPU6KaAPf7Nz/8Xlrg/2Cg3jjZm0B7xkA2q0wQUzGG83c oNtoExllCOdUg0LFo5F5mYzSG6ROKJTnucCrk9VgevYRfxNHnZdCMpIcGJ+8jp0u Rn/rdlPxwbY0eC1zilExafpHLBuaa70uuUqPRtWG7yJtgBwtQyQTLyPBr37bw7Mk POXZqXET1JdC+cJKulIU =sItt -----END PGP SIGNATURE----- _______________________________________________ varnish-misc mailing list [email protected] https://www.varnish-cache.org/lists/mailman/listinfo/varnish-misc
