I am roaming between several access points.  How do I know to which of them I am connected at any given moment?  Command line way is preferred.
I'm reposting  I asked on the  SE, bacause I have been redirected to Super User.  I have successfully set up two Linksys routers running DD-WRTv24 to do WDS. They have the same SSID, but different static local IP addresses. There is no security: it's just for testing; no Internet connection.   When I open my notebook, I see the SSID shared by the routers in the list of WiFi access points, and I can connect to it. Once connected, I can ping both routers' local IP addresses, so I know that the WDS is working. But I can't find a way to find out which of them I have actually connected to.  I wouldn't like to have different SSIDs, because I plan to have the access points hand-off users to one another, and I want it to be transparent for the users. I configured one AP to distribute DHCP IP addresses in one range, and the other in another range, so I can discover which AP I connected to at first, but I want a way to discover which AP I'm connected to now, so that I can find out whether the hand-off actually occurred.
Understand PAM and NSS In the last days I have set up some Linux system with LDAP authentication and everything works fine, but there's still something I can't really understand regarding NSS and PAM, also after a lot of research. Citing:  NSS allows administrators to specify a list of sources where authentication files, host names and other information will be stored and searched for  and  PAM is a set of libraries that provide a configurable authentication platform for applications and the underlying operating system  What I don't understand is how PAM and NSS work and interact together. In  the architecture is explained pretty well: I configure PAM to use pam_ldap for LDAP accounts and pam_unix for local accounts, then I configure nsswitch.conf to fetch information from local files and LDAP. If I have understood correctly LDAP is used twice: first by pam_ldap and then by NSS which is itself called from pam_unix. Is that right? Is LDAP really used twice? But why do I need to configure both NSS and PAM? My explanation is that PAM performs different tasks than NSS and it is used by other programs. But, then, it should be possible to use only NSS or only PAM, as I have read in . So I experimented a bit and I have first tried to delete LDAP from the nsswitch.conf (and the authentication stopped to work as if only pam_ldap is not enough to do the job). Then I re-enabled LDAP in NSS and I deleted it from the PAM configuration (this time everything worked fine, as if pam_ldap is useless and NSS is enough to authenticate a user). Is there anyone who can help me to clarify this? Many thanks in advance. UPDATE I've just tried something now. I removed again all the pam_ldap entries in all pam configuration fields and I have also removed shadow: ldap from nsswitch.conf. As now in all the system there are only the lines: passwd: ldap files and group: ldap files in nsswitch.conf. Well... the login with LDAP users works perfectly, those two lines (plus /etc/ldap.conf) are enough to configure LDAP auth. From my knowledge PAM in independent from NSS, but my tests showed it's not. So I ask myself is it possible to completely disable NSS and use only PAM? Indefinite article in title of thesis Using subcaption package but subfigures end up stacked rather than side by side how to replace multiple strings together in Oracle Google Mobile Friendly test shows "other error" for resource loads I get the error "Couldn't load 23 page resources" when doing the mobile friendly test at     However, the error message is (the rather unfriendly) "Other error."  When I visit the site in Chrome using Developer Tools and setting the device toolbar to "Responsive," it works fine with no errors, and when I go the Google Search Console and do Crawl->Fetch As Google, I get no errors. Combination with repetitions. 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For instance, the selected polygon in the screenshot has its longest segment from west to east so I would like to mark give the polygon the attribute W (for west) or either E (for east).   Is there any solution to solve my problem in a fast but generalized way?   I do not need very detailed results. It's just for the interpretation of a question.   I'm seeking an answer using ArcGIS 10.2 for Desktop.  To be more precise on what I'm looking for I try to explain more practical: I'm doing winderosion analysis for a specific area with 9000 fields. As result I have a potential susceptibility for each field. I like to check, if the fields with high susceptibility are correlated to a certain orientation of the fields, e.g. check if most of the fields with high risk are oriented in the main winddirection or not.   The search for the longest segment is not really important for me. It was just an idea I had to determine the direction. 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